About: I am a tech enthusiast who loves to build something all the time. Stay tuned to this channel for some amazing projects

Hello, Guys! My name is Navaneeth Krishnan. But I prefer The Tech Guy as my colleagues call me! So, I decided to document all the projects I do, so, now that I am documenting it, I thought it would be nice to do it in a tutorial form. So, here I am making the first tutorial for you guys!

I recently came to know about “BLYNK” which caught my attention since it is a mind blowing idea and the greatest part is they provide all the greatness for free! For those who haven’t heard about or if you want to know more about it visit the link below.

And one more thing before I start the instructable, i would like to inform you guys that all the projects that i make will be for sale.The link to this project is given below:



So, let me start off by saying what this project exactly is!

When you are done with this you will be able to connect your appliances to the world of the internet (nowadays called as IoT: Internet of Things) and connect them to your smartphones.

For instance, imagine you a had a hell lot of a day at your office and you come back home tired and sleepy. Then comes to the first obstacle parking your vehicle in your garage and there is great chance that you may have misplaced your garage door. no worry with this project when you reach home the phone’s GPS system detects it and sends the command to open the garage door for you and not only this… you can connect your light, fans and other appliances with this. You can set the security to turn on when you leave the house so that you can feel safe wherever you are. And of course, you will have the fun working with boards and codes and all….


The hardware consists of a development board based on wifi module

esp8266 called WeMos D1 which is Arduino compatible and can be programmed using Arduino IDE.A two channel relay is connected to the wemos and wemos connects to the free server provided by blynk to receive the commands send from the app made with blynk with a simple drag n drop feature. So basically, the app receives input from the user and sends to the server and the server sends it to your project hardware which is connected to the internet via Wi-Fi (you can also use ethernet with Arduino and an ethernet shield) which the server identifies with the unique auth token that you receive for every project that you make.


1. WeMos D1 R2.

2. a 4-channel relay.


Connect the VCC pin of the relay to the appropriate voltage(+5V or +12V)and GND pin to the GND pin of the WeMos D1. Now connect the 2 input pins to pins D2, D3 of the WeMos D1.That’s it you are all set to go. You connect your appliances the relay.

Step 5: CODE

For this you will need Arduino IDE, which can be downloaded from the link below:


After you are done with that you will have to do a couple of tinkering before you can start to upload the code.

1. You will need to download and install esp8266 board files for Arduino IDE.

2. Install the BLYNK library.

Once, you have finished the above two steps, you can download the code attached below and upload to your WeMos D1(Note: Don’t forget to change the board to your WeMos before that.) That’s it you are ready for the next step!


For blynk, the problem I was facing that I had to manually input the wifi SSID, wifi password and the auth token into the code itself and with a simple hack you can solve this issue. This hack was actually provided by one of the co-founders of blynk itself so you don’t need to feel guilty.

If you haven’t already, download the Blynk App from the Google Play store. Then open it, create an account and log in. Or, if you already have the Blynk app installed on your phone, make sure it’s updated to the latest release!(P.S. It is both available for android and IOS). Now, Open the app and create a new blynk account with your google account or facebook(I personally prefer Facebook, it is a lot more easier!).Click the QR-code icon in the top-right corner of the Blynk app (or the bigger icon on the main screen).and scan the QR code given in the images.(follow the screenshots ) That’s it you have done with the app setup too. Now, it's time to test the project.


First turn the hardware on and make sure all the connections are correct. Now open the blynk project and follow the screen shot to set up your hardware to your wifi network.

After you have setup your hardware, click the play button the top right corner to start the project. Now, You can control your appliances from anywhere in the world. If you run into any problem look up the next step


1. Double Check all the connections

2. Make sure the appropriate amount voltage is connected. 3. Make sure the internet is available. 4. Make sure you select the wifi router and give the correct password.

Internet of Things Contest 2017

Participated in the
Internet of Things Contest 2017