Ilaria  Dugg

Ilaria Dugg


Setup your Smart Home's Temperature and Humidity Monitoring Apps

1. Choose and setup hardware (sensors, receiver, Raspberry Pi) for a basic tracking tool on temperature and humidity

“How To: Smart Home setup to track indoor temperatures and humidity with sensors, Raspberry Pi, MQTT, Node.js, Vue.js and Chart.js”

Which (new) IoT hardware do we need for this setup?

  • RTL-SDR USB receiver: a cheap dongle that can be used as a computer based radio scanner for receiving live radio signals in your area (those gagdets receive signals from 500 kHz up to 1.75 GHz) (Amazon link)
  • Temperature / Humidity sensor: an even cheaper gagdet, that sends sensor data at 433 MHz into the area (e.g. as part of a “real” wheather station) (Amazon link)
  • Raspberry Pi 3 Model B: the small single-board computer servers as our heart and base station to receive and process sensor data, I have the Raspbian operating system installed. It could even serve as your web server later (if you are familiar with maintaining your own, but I will use a cloud service in this tutorial). (Amazon link)

At first, setup your sensors whereever you like in your appartment and connect your RTL-SDR receiver with the Raspberry Pi. How to receive the raw data out of the nearby area? A little open source software will help us with that: rtl_433 is a program (Github link) to decode traffic from devices that are broadcasting on 433.9 MHz. We install it on our Raspberry Pi:

# prepare os
sudo apt-get update
sudo apt-get upgrade
# install dependencies
sudo apt-get install libtool libusb-1.0.0-dev librtlsdr-dev rtl-sdr cmake
# clone rtl_433 Git Repository
git clone
# change to directory
cd rtl_433/
# make build folder
mkdir build
cd build/
# compile
cmake ../
# make
# install
sudo make install
# test if rtl_433 was properly installed
rtl_433 -h

After that we test if the program detects our RTL-SDR receiver with

rtl_433 -G

I had some trouble with the following error: _Kernel driver is active, or device is claimed by second instance of librtlsdr. __In the first case, please either detach or blacklist the kernel module _(dvb_usb_rtl28xxu), or enable automatic detaching at compile time.

The repository owner recommends

sudo rmmod dvb_usb_rtl28xxu rtl2832

in that case. If everything went well, the receiver is ready to get sensor data and rtl_433 helps with processing, so that after a few seconds you should get signals in the nearby area (yes, even temperature sensor data of your neighbor’s or sensor data of connected cars.)

This is image title

This is image title

Hurray, hardware is running!

2. Get and process your smart home sensor data with MQTT Broker Mosquitto and a Node.js backend application

“How To: Smart Home setup to track indoor temperatures and humidity with sensors, Raspberry Pi, MQTT, Node.js, Vue.js and Chart.js”

The main problem in this part is how to setup a stable and endlessly running task on a Raspberry Pi to continuesly receive the (correct!) sensor data. Secondly we want it to somehow process and transfer it to a service that works as our middleware to provide the frontend with JSON data to display. MQTT is the IoT protocol to go with but how can a MQTT broker like Mosquitto work with a Node.js backend properly?

Setup a web server backend with Node.js and Express.js

Multiple solutions would be possible here, but I decided for a Javascript Node.js backend which will be run with Express.js. Make sure node and npm are ready on your machine or install them first.

node -v
npm -v

Setup a project folder and a make a subfolder “server”. Create a new file “server.js” within and code a basic backend service. We will upgrade its functionality later.

const express = require('express');
const app = express();

// test
app.get('/', function (req, res) {
 res.send('hello world!');

app.listen(3000, () => console.log('App listening on port ', 3000));

Don’t forget to install the npm package express in your console and start the application!

npm init
npm install express --save
node server.js

Go to your browser and check if your web server works on http://localhost:3000.

Setup the MQTT broker Mosquitto

Why MQTT? The protocol is a lightweight publish/subscribe messaging transport solution which is very popular in the IoT field. We will use a MQTT broker as the control center to receive raw sensor data from our rtl_433 program, we installed in the previous chapter and forward them to our web server. Mosquitto is a common MQTT broker and is installed and tested on or Raspberry Pi with

sudo apt install -y mosquitto mosquitto-clients
mosquitto -v

The broker will be accessable to clients on mqtt://localhost:1883.

Setup a bash script that pipes received data to Mosquitto

The Raspberry Pi now gets the important task to not only start rtl_433 to decode traffic from devices that are broadcasting on 433.9 MHz manually, but to start this task on every reboot automatically. For that, we create a cronjob with the tool crontab, which should be installed on our system.

crontab -h

On your Raspberry Pi create a new file “” (or whatever you want) in your pi home folder and make it executable from your terminal:

chmod +x

After that, open the file in a text editor and add the following bash script. It will start rtl_433 and pipe the output in JSON format to Mosquitto, where it will be published in the topic “home/rtl_344”. Don’t forget to close and safe the file.

/usr/local/bin/rtl_433 -F json -M utc | mosquitto_pub -t home/rtl_433 -l

Now we can set up a new cronjob which will execute the shell script on every Raspberry Pi reboot. Open up a terminal:

# edit crontabs of user "pi"
crontab -e

# a text editor will open and load all existing cronjobs, add
@reboot sleep 60 && sh /home/pi/

Build a simple database with lowdb and Node.js

In development mode a very basic database will suffice our requirements, that’s why I used lowdb (Github link) to store the sensor data on localhost first. Lowdb is based on a JSON file in our project folder.

npm install lowdb --save

In your server.js add some code. Set some defaults first, which are required if your JSON file (mine is “db.json”) is empty at first.

const low = require('lowdb');
const FileSync = require('lowdb/adapters/FileSync')
const adapter = new FileSync('db.json');
const db = low(adapter);

db.defaults({ posts: [] })

That’s all. Now we can write into, edit and delete data within our database.

Consume MQTT sensor data and save it to the database

We go back to our Node.js application and install the MQTT client MQTT.js (Github link) to be able to consume data that is available via Mosquitto.

npm install mqtt --save

With the newly installed MQTT client we are able to receive all the messages that the MQTT broker delivers over its API on mqtt://localhost:1883. We now filter them to only process and store “correct” data sets (remember: our RTL-SDR receiver found signals from multiple IoT gagdets we are not interested in).

My setup included some buffer, temperature and date parsing, basic verifying and filtering regarding incoming messages before I stored the correct Javascript Objects into the lowdb. Continue working on your server.js:

const mqtt = require('mqtt');
const client = mqtt.connect(mqtt://localhost:1883);

fahrenheitToCelsius = (fahrenheit) => {
 var fTempVal = parseFloat(fahrenheit);
 var cTempVal = (fTempVal - 32) * (5 / 9);
 return (Math.round(cTempVal * 100) / 100);

client.on('message', function (topic, message) {
 // message is buffer
 var stringBuf = message && message.toString('utf-8')
 try {
   var json = JSON.parse(stringBuf);
   // console.log(json);
   if (json.model === 'inFactory sensor') {
     if ( === 91 || === 32) {
     // catch my specific sensor model
       if (json.temperature_F && json.humidity) {
       // add data to lowdb
       const time = moment.utc(json.time).tz("Europe/Berlin");
       const formattedTime = time.format('YYYY-MM-DD HH:mm:ss');
       console.log('write post');
       .push({ id: uuid.v1(), room:, temp: fahrenheitToCelsius(json.temperature_F), humidity: json.humidity, time: formattedTime }).write()
 } catch (e) {

That’s it. Whenever the MQTT client receives sensor data it will store it in our database accordingly. You can check that in your “db.json” file in your project folder, which grows bigger and bigger during runtime. It won’t delete itself on backend restart!

 "posts": [
 "id": "c107fc70-1f33-11e9-9b95-fbfea27c8046",
 "room": 32,
 "temp": 22.89,
 "humidity": 30,
 "time": "2019-01-23 18:24:34"
 "id": "6607f9f0-1f34-11e9-9b95-fbfea27c8046",
 "room": 32,
 "temp": 22.89,
 "humidity": 30,
 "time": "2019-01-23 18:29:11"
 "id": "16492190-1f35-11e9-9b95-fbfea27c8046",
 "room": 91,
 "temp": 22.72,
 "humidity": 35,
 "time": "2019-01-23 18:34:07"

Provide sensor data via REST API

Now that we have clean data in our lowdb we might want to provide them via a REST API to be consumable for a frontend or multiple frontends (smartphone app, web app, …). We already deployed a local web server running on Node.js and Express.js and can very simply add an endpoint the provides the database data with the following code. Add it to your server.js!

app.get('/api', (req, res) => {

Yes, that’s it. Check if it is working on http://localhost:3000/api or with your favourite REST client (e.g. Postman).

3. Display smart home data in a Quasar, Vue.js and Chart.js powered web application

“How To: Smart Home setup to track indoor temperatures and humidity with sensors, Raspberry Pi, MQTT, Node.js, Vue.js and Chart.js”

In this part we will build a basic dashboard displaying smart home sensor data with charts. We could go with whatever implementation you would like here: from vanilla HTML/CSS/JS to every framework which is suitable to our needs – which are basically doing an API call to our backend to fetch sensor data and lift them up to work nicely with a chart visualisation.

There are also other good solutions to deal with IoT frontends like Pimatic, OpenHAB and FHEM, but let’s just build this part completely on our own. We will go with the SPA framework Vue.js with Quasar on top: It comes with UI components in the popular Material Design, axios and some other features, that help getting started with Vue.js very fast.

Install the Vue.js (Link) and Quasar CLI (Github link) first!

npm install -g vue-cli
npm install -g quasar-cli

Go to your project root and init a new sub project for your frontend code with

quasar init vue-frontend

Now start you development server on http://localhost:8080/ with

quasar dev

and you are ready to develop your frontend according to your likes. Quasar comes with a basic starter layout including a side navigation. However we don’t need to work on this heavily and focus on the the homepage, where we will build the dashboard functionality.

Go to Index.vue and update the basic dashboard layout. You can use static images like in my proposal and put them into the src/assets folder.

 <q-page padding class="docs-input row justify-center">
   <div class="row gutter-sm">
     <div class="col-6">
       <q-card inline>
         <q-card-media style="max-height: 250px">
            <img src="~assets/temperature.jpg">
             <q-card-title slot="overlay">
               <span slot="subtitle">hot or not</span>
         <q-card-main>lorem ipsum</q-card-main>
 <div class="col-6">
   <q-card inline>
     <q-card-media style="max-height: 250px">
       <img src="~assets/humidity.jpg">
       <q-card-title slot="overlay">
         <span slot="subtitle">some like it wet</span>
     <q-card-main>lorem ipsum</q-card-main>


  export default {
  name: "PageIndex"

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Fetch sensor data from Node.js backend

To fetch necessary data on page load we make use of Vue.js’ created() function in the section below the template. We insert a new function this.fetchData(); there and implement this new function in the methods’ block.

methods: {
  fetchData() {
   this.loaded = false;
    .then(response => {
    .then(response => {
      this.loaded = true;
    .catch(e => {
       color: "negative",
       position: "top",
       message: "Could not fetch.",
       icon: "report_problem"

We simply use the axios library (Github link) which Quasar included right from the setup, so we can use it globally without importing it explicitly. If this works properly you should be able to log the array of sensor data in your browser’s developer tools. If there is any problem, we trigger the Quasar component notification and include the error message.

Hint: If you encounter CORS problems in the communication between front- and backend (e. g. “No Access-Control-Allow-Origin header is present on the requested resource.”) edit your server.js and restart it as follows:

app.use(function (req, res, next) {
 res.header("Access-Control-Allow-Origin", "*");
 res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
Build a line chart with Chart.js

In this part I will focus on displaying only the temperature chart to make the tutorial more comprehensable. At first we will install the npm package vue-chartjs (Github link) which works as a practical Vue.js wrapper for Chart.js (Link).

npm install vue-chartsjs --save

Now we build a generic, reusable line chart component to use in the web application. Create a new file “LineChart.js” in the src/components folder and import the vue-chartsjs package. Furthermore, we will follow the basic tutorial for the package and specify a data collection prop and an options prop that will prettify our line chart later.

import { Line } from 'vue-chartjs';

export default {
 extends: Line,
 props: {
   datacollection: {
    type: Object,
    default: null
   options: {
    type: Object,
    default: null
 mounted() {
   this.renderChart(this.datacollection, this.options, {responsive: true})

Switch to the Index.vue again and include a new line chart component (html tag) in your template. We want to display it within the card component. Additionally we specify some properties: v-if=”loaded” will tell the component that it should only mount, if the according data prop is true. Also, we transfer the fetched datacollection_humidity and options_humidity as our generic datacollection and options into the line chart.


We also have to edit our fetchData(); function and transfer the fetched data as a processible JSON to the data collection prop.

// process the backend response and add labels and some styling for the Chart.js api  
const datacollection_humidity = {
   labels: => obj.time),
   datasets: [
       label: "Humidity",
       backgroundColor: "#000",
       data: => obj.humidity)

this.datacollection_humidity = datacollection_humidity;

// set some optional properties regarding axes and ticks
this.options_humidity = {
   scales: {
   xAxes: [
       type: "time",
       distribution: "linear"
   yAxes: [
       scaleLabel: {
       display: true
   ticks: {
     callback: function(value, index, values) {
       return value + "%";

Don’t forget to add the LineChart component and the necessary “loaded” data prop in your Vue.js section.

export default {
 name: "PageIndex",
 components: {
 data() {
   return {
     loaded: false,

That’s it! On every page reload, the web application fetches available sensor data from our backend service and will display it as a line chart. You would like to add more functionality? You can find all features we built and more (filtering, reloading, deploying, saving persistently, …) in my Github repository for this project.

I hope this tutorial will surely help and you if you liked this tutorial, please consider sharing it with others. Always warm in your smart home …

Thank you for reading!

#node-js #vue-js #javascript #json #web-development

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Setup your Smart Home's Temperature and Humidity Monitoring Apps
Carmen  Grimes

Carmen Grimes


How to start an electric scooter facility/fleet in a university campus/IT park

Are you leading an organization that has a large campus, e.g., a large university? You are probably thinking of introducing an electric scooter/bicycle fleet on the campus, and why wouldn’t you?

Introducing micro-mobility in your campus with the help of such a fleet would help the people on the campus significantly. People would save money since they don’t need to use a car for a short distance. Your campus will see a drastic reduction in congestion, moreover, its carbon footprint will reduce.

Micro-mobility is relatively new though and you would need help. You would need to select an appropriate fleet of vehicles. The people on your campus would need to find electric scooters or electric bikes for commuting, and you need to provide a solution for this.

To be more specific, you need a short-term electric bike rental app. With such an app, you will be able to easily offer micro-mobility to the people on the campus. We at Devathon have built Autorent exactly for this.

What does Autorent do and how can it help you? How does it enable you to introduce micro-mobility on your campus? We explain these in this article, however, we will touch upon a few basics first.

Micro-mobility: What it is


You are probably thinking about micro-mobility relatively recently, aren’t you? A few relevant insights about it could help you to better appreciate its importance.

Micro-mobility is a new trend in transportation, and it uses vehicles that are considerably smaller than cars. Electric scooters (e-scooters) and electric bikes (e-bikes) are the most popular forms of micro-mobility, however, there are also e-unicycles and e-skateboards.

You might have already seen e-scooters, which are kick scooters that come with a motor. Thanks to its motor, an e-scooter can achieve a speed of up to 20 km/h. On the other hand, e-bikes are popular in China and Japan, and they come with a motor, and you can reach a speed of 40 km/h.

You obviously can’t use these vehicles for very long commutes, however, what if you need to travel a short distance? Even if you have a reasonable public transport facility in the city, it might not cover the route you need to take. Take the example of a large university campus. Such a campus is often at a considerable distance from the central business district of the city where it’s located. While public transport facilities may serve the central business district, they wouldn’t serve this large campus. Currently, many people drive their cars even for short distances.

As you know, that brings its own set of challenges. Vehicular traffic adds significantly to pollution, moreover, finding a parking spot can be hard in crowded urban districts.

Well, you can reduce your carbon footprint if you use an electric car. However, electric cars are still new, and many countries are still building the necessary infrastructure for them. Your large campus might not have the necessary infrastructure for them either. Presently, electric cars don’t represent a viable option in most geographies.

As a result, you need to buy and maintain a car even if your commute is short. In addition to dealing with parking problems, you need to spend significantly on your car.

All of these factors have combined to make people sit up and think seriously about cars. Many people are now seriously considering whether a car is really the best option even if they have to commute only a short distance.

This is where micro-mobility enters the picture. When you commute a short distance regularly, e-scooters or e-bikes are viable options. You limit your carbon footprints and you cut costs!

Businesses have seen this shift in thinking, and e-scooter companies like Lime and Bird have entered this field in a big way. They let you rent e-scooters by the minute. On the other hand, start-ups like Jump and Lyft have entered the e-bike market.

Think of your campus now! The people there might need to travel short distances within the campus, and e-scooters can really help them.

How micro-mobility can benefit you


What advantages can you get from micro-mobility? Let’s take a deeper look into this question.

Micro-mobility can offer several advantages to the people on your campus, e.g.:

  • Affordability: Shared e-scooters are cheaper than other mass transportation options. Remember that the people on your campus will use them on a shared basis, and they will pay for their short commutes only. Well, depending on your operating model, you might even let them use shared e-scooters or e-bikes for free!
  • Convenience: Users don’t need to worry about finding parking spots for shared e-scooters since these are small. They can easily travel from point A to point B on your campus with the help of these e-scooters.
  • Environmentally sustainable: Shared e-scooters reduce the carbon footprint, moreover, they decongest the roads. Statistics from the pilot programs in cities like Portland and Denver showimpressive gains around this key aspect.
  • Safety: This one’s obvious, isn’t it? When people on your campus use small e-scooters or e-bikes instead of cars, the problem of overspeeding will disappear. you will see fewer accidents.

#android app #autorent #ios app #mobile app development #app like bird #app like bounce #app like lime #autorent #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

Carmen  Grimes

Carmen Grimes


Best Electric Bikes and Scooters for Rental Business or Campus Facility

The electric scooter revolution has caught on super-fast taking many cities across the globe by storm. eScooters, a renovated version of old-school scooters now turned into electric vehicles are an environmentally friendly solution to current on-demand commute problems. They work on engines, like cars, enabling short traveling distances without hassle. The result is that these groundbreaking electric machines can now provide faster transport for less — cheaper than Uber and faster than Metro.

Since they are durable, fast, easy to operate and maintain, and are more convenient to park compared to four-wheelers, the eScooters trend has and continues to spike interest as a promising growth area. Several companies and universities are increasingly setting up shop to provide eScooter services realizing a would-be profitable business model and a ready customer base that is university students or residents in need of faster and cheap travel going about their business in school, town, and other surrounding areas.

Electric Scooters Trends and Statistics

In many countries including the U.S., Canada, Mexico, U.K., Germany, France, China, Japan, India, Brazil and Mexico and more, a growing number of eScooter users both locals and tourists can now be seen effortlessly passing lines of drivers stuck in the endless and unmoving traffic.

A recent report by McKinsey revealed that the E-Scooter industry will be worth― $200 billion to $300 billion in the United States, $100 billion to $150 billion in Europe, and $30 billion to $50 billion in China in 2030. The e-Scooter revenue model will also spike and is projected to rise by more than 20% amounting to approximately $5 billion.

And, with a necessity to move people away from high carbon prints, traffic and congestion issues brought about by car-centric transport systems in cities, more and more city planners are developing more bike/scooter lanes and adopting zero-emission plans. This is the force behind the booming electric scooter market and the numbers will only go higher and higher.

Companies that have taken advantage of the growing eScooter trend develop an appthat allows them to provide efficient eScooter services. Such an app enables them to be able to locate bike pick-up and drop points through fully integrated google maps.

List of Best Electric Bikes for Rental Business or Campus Facility 2020:

It’s clear that e scooters will increasingly become more common and the e-scooter business model will continue to grab the attention of manufacturers, investors, entrepreneurs. All this should go ahead with a quest to know what are some of the best electric bikes in the market especially for anyone who would want to get started in the electric bikes/scooters rental business.

We have done a comprehensive list of the best electric bikes! Each bike has been reviewed in depth and includes a full list of specs and a photo.

Billy eBike


To start us off is the Billy eBike, a powerful go-anywhere urban electric bike that’s specially designed to offer an exciting ride like no other whether you want to ride to the grocery store, cafe, work or school. The Billy eBike comes in 4 color options – Billy Blue, Polished aluminium, Artic white, and Stealth black.

Price: $2490

Available countries

Available in the USA, Europe, Asia, South Africa and Australia.This item ships from the USA. Buyers are therefore responsible for any taxes and/or customs duties incurred once it arrives in your country.


  • Control – Ride with confidence with our ultra-wide BMX bars and a hyper-responsive twist throttle.
  • Stealth- Ride like a ninja with our Gates carbon drive that’s as smooth as butter and maintenance-free.
  • Drive – Ride further with our high torque fat bike motor, giving a better climbing performance.
  • Accelerate – Ride quicker with our 20-inch lightweight cutout rims for improved acceleration.
  • Customize – Ride your own way with 5 levels of power control. Each level determines power and speed.
  • Flickable – Ride harder with our BMX /MotoX inspired geometry and lightweight aluminum package


  • Maximum speed: 20 mph (32 km/h)
  • Range per charge: 41 miles (66 km)
  • Maximum Power: 500W
  • Motor type: Fat Bike Motor: Bafang RM G060.500.DC
  • Load capacity: 300lbs (136kg)
  • Battery type: 13.6Ah Samsung lithium-ion,
  • Battery capacity: On/off-bike charging available
  • Weight: w/o batt. 48.5lbs (22kg), w/ batt. 54lbs (24.5kg)
  • Front Suspension: Fully adjustable air shock, preload/compression damping /lockout
  • Rear Suspension: spring, preload adjustment
  • Built-in GPS

Why Should You Buy This?

  • Riding fun and excitement
  • Better climbing ability and faster acceleration.
  • Ride with confidence
  • Billy folds for convenient storage and transportation.
  • Shorty levers connect to disc brakes ensuring you stop on a dime
  • belt drives are maintenance-free and clean (no oil or lubrication needed)

**Who Should Ride Billy? **

Both new and experienced riders

**Where to Buy? **Local distributors or ships from the USA.

Genze 200 series e-Bike


Featuring a sleek and lightweight aluminum frame design, the 200-Series ebike takes your riding experience to greater heights. Available in both black and white this ebike comes with a connected app, which allows you to plan activities, map distances and routes while also allowing connections with fellow riders.

Price: $2099.00

Available countries

The Genze 200 series e-Bike is available at GenZe retail locations across the U.S or online via website. Customers from outside the US can ship the product while incurring the relevant charges.


  • 2 Frame Options
  • 2 Sizes
  • Integrated/Removable Battery
  • Throttle and Pedal Assist Ride Modes
  • Integrated LCD Display
  • Connected App
  • 24 month warranty
  • GPS navigation
  • Bluetooth connectivity


  • Maximum speed: 20 mph with throttle
  • Range per charge: 15-18 miles w/ throttle and 30-50 miles w/ pedal assist
  • Charging time: 3.5 hours
  • Motor type: Brushless Rear Hub Motor
  • Gears: Microshift Thumb Shifter
  • Battery type: Removable Samsung 36V, 9.6AH Li-Ion battery pack
  • Battery capacity: 36V and 350 Wh
  • Weight: 46 pounds
  • Derailleur: 8-speed Shimano
  • Brakes: Dual classic
  • Wheels: 26 x 20 inches
  • Frame: 16, and 18 inches
  • Operating Mode: Analog mode 5 levels of Pedal Assist Thrott­le Mode

Norco from eBikestore


The Norco VLT S2 is a front suspension e-Bike with solid components alongside the reliable Bosch Performance Line Power systems that offer precise pedal assistance during any riding situation.

Price: $2,699.00

Available countries

This item is available via the various Norco bikes international distributors.


  • VLT aluminum frame- for stiffness and wheel security.
  • Bosch e-bike system – for their reliability and performance.
  • E-bike components – for added durability.
  • Hydraulic disc brakes – offer riders more stopping power for safety and control at higher speeds.
  • Practical design features – to add convenience and versatility.


  • Maximum speed: KMC X9 9spd
  • Motor type: Bosch Active Line
  • Gears: Shimano Altus RD-M2000, SGS, 9 Speed
  • Battery type: Power Pack 400
  • Battery capacity: 396Wh
  • Suspension: SR Suntour suspension fork
  • Frame: Norco VLT, Aluminum, 12x142mm TA Dropouts

Bodo EV


Manufactured by Bodo Vehicle Group Limited, the Bodo EV is specially designed for strong power and extraordinary long service to facilitate super amazing rides. The Bodo Vehicle Company is a striking top in electric vehicles brand field in China and across the globe. Their Bodo EV will no doubt provide your riders with high-level riding satisfaction owing to its high-quality design, strength, breaking stability and speed.

Price: $799

Available countries

This item ships from China with buyers bearing the shipping costs and other variables prior to delivery.


  • Reliable
  • Environment friendly
  • Comfortable riding
  • Fashionable
  • Economical
  • Durable – long service life
  • Braking stability
  • LED lighting technology


  • Maximum speed: 45km/h
  • Range per charge: 50km per person
  • Charging time: 8 hours
  • Maximum Power: 3000W
  • Motor type: Brushless DC Motor
  • Load capacity: 100kg
  • Battery type: Lead-acid battery
  • Battery capacity: 60V 20AH
  • Weight: w/o battery 47kg

#android app #autorent #entrepreneurship #ios app #minimum viable product (mvp) #mobile app development #news #app like bird #app like bounce #app like lime #autorent #best electric bikes 2020 #best electric bikes for rental business #best electric kick scooters 2020 #best electric kickscooters for rental business #best electric scooters 2020 #best electric scooters for rental business #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

Fredy  Larson

Fredy Larson


How long does it take to develop/build an app?

With more of us using smartphones, the popularity of mobile applications has exploded. In the digital era, the number of people looking for products and services online is growing rapidly. Smartphone owners look for mobile applications that give them quick access to companies’ products and services. As a result, mobile apps provide customers with a lot of benefits in just one device.

Likewise, companies use mobile apps to increase customer loyalty and improve their services. Mobile Developers are in high demand as companies use apps not only to create brand awareness but also to gather information. For that reason, mobile apps are used as tools to collect valuable data from customers to help companies improve their offer.

There are many types of mobile applications, each with its own advantages. For example, native apps perform better, while web apps don’t need to be customized for the platform or operating system (OS). Likewise, hybrid apps provide users with comfortable user experience. However, you may be wondering how long it takes to develop an app.

To give you an idea of how long the app development process takes, here’s a short guide.

App Idea & Research


_Average time spent: two to five weeks _

This is the initial stage and a crucial step in setting the project in the right direction. In this stage, you brainstorm ideas and select the best one. Apart from that, you’ll need to do some research to see if your idea is viable. Remember that coming up with an idea is easy; the hard part is to make it a reality.

All your ideas may seem viable, but you still have to run some tests to keep it as real as possible. For that reason, when Web Developers are building a web app, they analyze the available ideas to see which one is the best match for the targeted audience.

Targeting the right audience is crucial when you are developing an app. It saves time when shaping the app in the right direction as you have a clear set of objectives. Likewise, analyzing how the app affects the market is essential. During the research process, App Developers must gather information about potential competitors and threats. This helps the app owners develop strategies to tackle difficulties that come up after the launch.

The research process can take several weeks, but it determines how successful your app can be. For that reason, you must take your time to know all the weaknesses and strengths of the competitors, possible app strategies, and targeted audience.

The outcomes of this stage are app prototypes and the minimum feasible product.

#android app #frontend #ios app #minimum viable product (mvp) #mobile app development #web development #android app development #app development #app development for ios and android #app development process #ios and android app development #ios app development #stages in app development

YuccaPrerenderBundle: Symfony2 Bundle to Use


Backbone, EmberJS, Angular and so more are your daily basis ? In case of an admin area, that's fine, but on your front office, you might encounter some SEO problems

Thanks to, you now can dynamically render your JavaScript pages in your server using PhantomJS.

This bundle is largely inspired by bakura10 work on zfr-prerender


Install the module by typing (or add it to your composer.json file):

$ php composer.phar require "yucca/prerender-bundle" "0.1.*@dev"

Register the bundle in app/AppKernel.php:

// app/AppKernel.php
public function registerBundles()
    return array(
        // ...
        new Yucca\PrerenderBundle\YuccaPrerenderBundle(),

Enable the bundle's configuration in app/config/config.yml:

# app/config/config.yml
yucca_prerender: ~


How it works

  1. Check to make sure we should show a prerendered page
    1. Check if the request is from a crawler (agent string)
    2. Check to make sure we aren't requesting a resource (js, css, etc...)
    3. (optional) Check to make sure the url is in the whitelist
    4. (optional) Check to make sure the url isn't in the blacklist
  2. Make a GET request to the prerender service (PhantomJS server) for the page's prerendered HTML
  3. Return that HTML to the crawler


This bundle comes with a sane default, extracted from prerender-node middleware, but you can easily customize it:


Prerender URL

By default, YuccaPrerenderBundle uses the service deployed at However, you may want to deploy it on your own server. To that extent, you can customize YuccaPrerenderBundle to use your server using the following configuration:

    backend_url: http://localhost:3000

With this config, here is how YuccaPrerender will proxy the "" request:

GET http://localhost:3000/

Crawler user-agents

YuccaPrerender decides to pre-render based on the User-Agent string to check if a request comes from a bot or not. By default, those user agents are registered: 'baiduspider', 'facebookexternalhit', 'twitterbot'. Googlebot, Yahoo, and Bingbot should not be in this list because we support escaped_fragment instead of checking user agent for those crawlers. Your site must have to understand the '#!' ajax url notation.

You can add other User-Agent string to evaluate using this sample configuration:

    crawler_user_agents: ['yandex', 'msnbot']

Ignored extensions

YuccaPrerender is configured by default to ignore all the requests for resources with those extensions: .js, .css, .less, .png, .jpg, .jpeg, .gif, .pdf, .doc, .txt, .zip, .mp3, .rar, .exe, .wmv, .doc, .avi, .ppt, .mpg, .mpeg, .tif, .wav, .mov, .psd, .ai, .xls, .mp4, .m4a, .swf, .dat, .dmg, .iso, .flv, .m4v, .torrent . Those are never pre-rendered.

You can add your own extensions using this sample configuration:

    ignored_extensions: ['.less', '.pdf']


Whitelist a single url path or multiple url paths. Compares using regex, so be specific when possible. If a whitelist is supplied, only url's containing a whitelist path will be prerendered.

Here is a sample configuration that only pre-render URLs that contains "/users/":

    whitelist_urls: ['/users/*']

Note: remember to specify URL here and not Symfony2 route names.


Blacklist a single url path or multiple url paths. Compares using regex, so be specific when possible. If a blacklist is supplied, all url's will be pre-rendered except ones containing a blacklist part. Please note that if the referer is part of the blacklist, it won't be pre-rendered too.

Here is a sample configuration that prerender all URLs excepting the ones that contains "/users/":

    blacklist_urls: ['/users/*']

Note: remember to specify URL here and not Symfony22 route names.


If you want to make sure your pages are rendering correctly:

  1. Open the Developer Tools in Chrome (Cmd + Atl + J)
  2. Click the Settings gear in the bottom right corner.
  3. Click "Overrides" on the left side of the settings panel.
  4. Check the "User Agent" checkbox.
  5. Choose "Other..." from the User Agent dropdown.
  6. Type googlebot into the input box.
  7. Refresh the page (make sure to keep the developer tools open).


  • Thanks to bakura10 for the Zend Framework version.
  • Thanks to Romain Boyer to make me discover
  • Thanks to the prerender team and all JS MVC developpers

Author: rjanot
Source Code: 
License: MIT License

#php #symfony 

ThruwayBundle: Bundle for Building Real-time Apps in Symfony


This a Symfony Bundle for Thruway, which is a php implementation of WAMP (Web Application Messaging Protocol).

Note: This project is still undergoing a lot of changes, so the API will change.

Quick Start with Composer

Install the Thruway Bundle

  $ composer require "voryx/thruway-bundle"

Update AppKernel.php (when using Symfony < 4)

$bundles = array(
    // ...
    new Voryx\ThruwayBundle\VoryxThruwayBundle(),
    // ...



    realm: 'realm1'
    url: 'ws://' #The url that the clients will use to connect to the router
        ip: ''  # the ip that the router should start on
        port: '8080'  # public facing port.  If authentication is enabled, this port will be protected
        trusted_port: '8081' # Bypasses all authentication.  Use this for trusted clients.
#        authentication: false # true will load the AuthenticationManager
        bundles: ["AppBundle"]
#        files:
#            - "Acme\\DemoBundle\\Controller\\DemoController"
# For symfony 4, this bundle will automatically scan for annotated worker files in the src/Controller folder

With Symfony 4 use a filename like: config/packages/voryx.yaml

If you are using the in-memory user provider, you'll need to add a thruway to the security firewall and set the in_memory_user_provider.


            security: false	     

You can also tag services with thruway.resource and any annotation will get picked up

<service id="some.service" class="Acme\Bundle\SomeService">
    <tag name="thruway.resource"/>

Note: tagging a service as thruway.resource will make it public.

        resource: '../src/Worker'
        tags: ['thruway.resource']

Authentication with FOSUserBundle via WampCRA

Change the Password Encoder (tricky on existing sites) to master wamp challenge


            algorithm:            pbkdf2
            hash_algorithm:       sha256
            encode_as_base64:     true
            iterations:           1000
            key_length:           32

set voryx_thruway.user_provider to "fos_user.user_provider"


    user_provider: 'fos_user.user_provider.username' #fos_user.user_provider.username_email login with email

The WAMP-CRA service is already configured, we just need to add a tag to it to have the bundle install it:

        class: Thruway\Authentication\WampCraAuthProvider
        parent: voryx.thruway.wamp.cra.auth.client
            - { name: thruway.internal_client }

Custom Authorization Manager

You can set your own Authorization Manager in order to check if a user (identified by its authid) is allowed to publish | subscribe | call | register

Create your Authorization Manager service, extending RouterModuleClient and implementing RealmModuleInterface (see the Thruway doc for details)

// src/ACME/AppBundle/Security/MyAuthorizationManager.php

use Thruway\Event\MessageEvent;
use Thruway\Event\NewRealmEvent;
use Thruway\Module\RealmModuleInterface;
use Thruway\Module\RouterModuleClient;

class MyAuthorizationManager extends RouterModuleClient implements RealmModuleInterface
     * Listen for Router events.
     * Required to add the authorization module to the realm
     * @return array
    public static function getSubscribedEvents()
        return [
            'new_realm' => ['handleNewRealm', 10]

     * @param NewRealmEvent $newRealmEvent
    public function handleNewRealm(NewRealmEvent $newRealmEvent)
        $realm = $newRealmEvent->realm;

        if ($realm->getRealmName() === $this->getRealm()) {

     * @return array
    public function getSubscribedRealmEvents()
        return [
            'PublishMessageEvent'   => ['authorize', 100],
            'SubscribeMessageEvent' => ['authorize', 100],
            'RegisterMessageEvent'  => ['authorize', 100],
            'CallMessageEvent'      => ['authorize', 100],

     * @param MessageEvent $msg
     * @return bool
    public function authorize(MessageEvent $msg)
        if ($msg->session->getAuthenticationDetails()->getAuthId() === 'username') {
            return true;
        return false;

Register your authorization manager service

        class: ACME\AppBundle\Security\MyAuthorizationManager

Insert your service name in the voryx_thruway config


        authorization: my_authorization_manager # insert the name of your custom authorizationManager

Restart the Thruway server; it will now check authorization upon publish | subscribe | call | register. Remember to catch error when you try to subscribe to a topic (or any other action) as it may now be denied and this will be returned as an error.


Register RPC

    use Voryx\ThruwayBundle\Annotation\Register;
     * @Register("com.example.add")
    public function addAction($num1, $num2)
        return $num1 + $num2;

Call RPC

    public function call($value)
        $client = $this->container->get('thruway.client');
        $client->call("com.myapp.add", [2, 3])->then(
            function ($res) {
                echo $res[0];


     use Voryx\ThruwayBundle\Annotation\Subscribe;

     * @Subscribe("com.example.subscribe")
    public function subscribe($value)
        echo $value;


    public function publish($value)
        $client = $this->container->get('thruway.client');
        $client->publish("com.myapp.hello_pubsub", [$value]);

It uses Symfony Serializer, so it can serialize and deserialize Entities

         use Voryx\ThruwayBundle\Annotation\Register;

     * @Register("com.example.addrpc", serializerEnableMaxDepthChecks=true)
    public function addAction(Post $post)
        //Do something to $post

        return $post;

Start the Thruway Process

You can start the default Thruway workers (router and client workers), without any additional configuration.

$ nohup php app/console thruway:process start &

By default, the router starts on ws://


The Thruway bundle will start up a separate process for the router and each defined worker. If you haven't defined any workers, all of the annotated calls and subscriptions will be started within the default worker.

There are two main ways to break your application apart into multiple workers.

Use the worker property on the Register and Subscribe annotations. The following RPC will be added to the posts worker.

  use Voryx\ThruwayBundle\Annotation\Register;

  * @Register("com.example.addrpc", serializerEnableMaxDepthChecks=true, worker="posts")
  public function addAction(Post $post)

Use the @Worker annotation on the class. The following annotation will create a worker called chat that can have a max of 5 instances.

  use Voryx\ThruwayBundle\Annotation\Worker;

  * @Worker("chat", maxProcesses="5")
  class ChatController

If a worker is shut down with anything other than SIGTERM, it will automatically be restarted.

More Commands

To see a list of running processes (workers)

$ php app/console thruway:process status

Stop a process, i.e. default

$ php app/console thruway:process stop default

Start a process, i.e. default

$ php app/console thruway:process start default

Javascript Client

For the client, you can use AutobahnJS or any other WAMPv2 compatible client.

Here are some examples

Symfony 4 Quick Start

composer create-project symfony/skeleton my_project
cd my_project
composer require symfony/expression-language
composer require symfony/annotations-pack
composer require voryx/thruway-bundle:dev-master

Create config/packages/my_project.yml with the following config:

    realm: 'realm1'
    url: 'ws://' #The url that the clients will use to connect to the router
        ip: ''  # the ip that the router should start on
        port: '8080'  # public facing port.  If authentication is enabled, this port will be protected
        trusted_port: '8081' # Bypasses all authentication.  Use this for trusted clients.

Create the controller src/Controller/TestController.php

namespace App\Controller;

use Voryx\ThruwayBundle\Annotation\Register;

class TestController
     * @Register("com.example.add")
    public function addAction($num1, $num2)
        return $num1 + $num2;

Test to see if the RPC has been configured correctly bin/console thruway:debug

 URI             Type Worker  File                                                  Method    
 com.example.add RPC  default /my_project/src/Controller/TestController.php         addAction 

For more debug info for the RPC we created: bin/console thruway:debug com.example.add

Start everything: bin/console thruway:process start

The RPC com.example.add is now available to any WAMP client connected to ws:// on realm1.

Author: Voryx
Source Code: 

#php #symfony