As you may have noticed from some of the other posts, I use App Inventor 2 to create Android apps. I do not have time to learn JAVA programming and I found App Inventor an easy way to get in to the world of Android apps. AI2 is not perfect. It is designed as a teaching aid rather than a fully featured Android programming language and as such there are many things missing. However, you can create some surprisingly advanced apps with it. The Arduino Bluetooth Control and the dropController apps were created in AI2 as is the new Bluetooth Control Panel app.
Controlling an Arduino over Bluetooth from Android using App Inventor 2
Here is an example of controlling the Arduino over Bluetooth using a HC-06 bluetooth module and an Android app. The example uses an Arduino Nano but other Arduinos will work just as well. A HC-05 module can be used stead of the HC-06.
The Android app was created in app inventor and the aia file can be downloaded at the bottom of the page.
In the first part I showed how to control a single LED from an app created in App Inventor. This worked OK but was very limited. You could control only 1 LED and the control was one way; from the app to the Arduino. What if you want to have 2 way control of the LED and to be able to also control the LED from the Arduino side? What if you want to control more than 1 LED?
In this guide we look at adding two-way communication. Here we control an LED but you could have it doing anything.
In first example you could only control the LED from the Android app, here we extend the example so that we can also control the LED at the Arduino side. When the LED is turned on or off by the Arduino we want the button in the app to update to show the correct LED status.
The first example used methods only suitable for controlling one LED, this time we will try to make it so the Arduino sketch and also the AI2 app can be easily scaled and so once you have the basic app in place adding extra buttons and controls should be fairly straight forward.
Although I use a HC-06 in the below examples the HC-05 in slave mode can also be used.
Using MITs app inventor it is fairly easy to create an app that can turn a LED on and off from an Android device.
This is a fairly simply example of sending commands to the Arduino to turn a LED either on or off. The Android app sends ascii codes to the Arduino via the HC-06 BT module; “ON” for on and “OF” for off.
Load the app, connect to the HC-06 and then use the LED button to turn the LED on and off.
You can also open the serial monitor to see the commands as they are received