To remotely control hardware, we need separate communication tools. Typically, we use Bluetooth, BLE, Ethernet, or WiFi. We can easily control communication devices by using a smartphone app without a physical controller. However, creating a custom app is quite difficult. So, I’d like to introduce the Blynk Server, which can be easily implemented on any app!


Blynk is an application that allows the user to configure the controller and monitor the Arduino. It is a way to communicate between the Blynk app and the Arduino via the Blynk server.


A simple tutorial can be found at the above link.
Equip Arduino Mega with W5100 Ethernet Shield.
Then select the hardware and communication method that you want to use.
Create a Widget Box and you can program the Widget by the code.
Each Widget can be assigned a pin number.
The code identifies the Widget Box via pin number.

Blynk Display

You can display and control using Blynk.
By accepting the Arduino sensor value, the Blynk app can accept input and display the value, or even output to control the sensor through the app.

source :

In the link above, the author implemented the Ethernet Shield onto Arduino Uno to display the sensor value on the Blynk app.
Blynk.virtualWrite(V5, celsius);

If you write the code like above, the virtual number V5 will be written as the sensor value and be displayed on Blynk. We used Value Display, LCD, Terminal, and SuperChart in order of WidgetBox.

Blynk Control


source :

You can see that Arduino Uno is equipped with Ethernet Shield to control LED in the link above.
In the case of a simple control, such as a button, it is implemented to be controlled in the Blynk Library.
You can control it simply by matching the pin number of the Widget Box with the pin number of the sensor connected to Arduino and running Blynk.


You can also control RGB LED through a slider as well as a button.

You can learn more about WidgetBox on the Blynk homepage.

As you can see, you can control and monitor any sensor through Blynk.
Select your favorite Widget Box and let’s create our very own IoT system!

Author : Becky