Using this extension you can create a serial connection via USB between your phone and an Arduino


Extension Developer Pavitra
Clone Starter .aia Open in Thunkable
Get the .aix Manual Download
Click-to-Copy Link com.pavitra.Arduino
Donate to Developer N/A
License Apache 2.0

Thunkable Community

If you have any questions about the Arduino USB Serial extension then head on over to the Thunkable Community where you’ll find lots of amazing people who are happy to help you out.


Starting a Connection


Is Open

Transmit and Receive Data

Once the connection has been established you can read data from the Arduino and write data to it via the read and write blocks.

Read Write

Note that the default baud rate is 9600 bps.

Managing the Connection

You can open and close the connection with the open and close blocks.

Open Close


Arduino Object


Here are a few screenshots to help you out with some common errors that can occur when using this extension. If you encounter any more please get in touch.


Make sure that you are using the USB Media Transfer Protocol when that Arduino is connected to your phone. The exact location will vary from phone to phone, but if you search in Settings for “USB” you should find it. On many phones, when you connect a USB device it asks you what sort of connection you would like and you can change to MTP at this stage. Configuration


When you launch the app for the first time you should be asked for permission to access the USB device like so: Permission If you click “Cancel” the app will not be able to communicate with the Arduino

Runtime Error

This error occurs when the app is unable to communicate with the Arduino. Run Time Error It can be useful to have some sort of “refresh” button in your app to close and the open the connection to minimise these errors.