Tutorials in English:
https://www.instructables.com/id/Controlling-a-Roomba-Robot-With-Arduino-and-Androi/
https://www.hackster.io/mjrobot/controlling-a-roomba-robot-with-arduino-and-android-device-56970d
Tutorial in Portuguese:
https://mjrobot.org/2016/07/04/controlando-o-robo-aspirador-roomba-com-arduino-e-android/
NOTE: App is not availabe at PlayStore
BT Remote control was deveveloped using AppInventor from MIT. Here the link for downloading or changing the project:
http://ai2.appinventor.mit.edu/?galleryId=6472968488615936
Alternatevelly, the files generated using AppInventor can be found here on their specific folder /App_Inventor:
- MJRoBot_II_BT_Command_V2.aia (Source code to replicate/change the app using MIT AppInventor)
- MJRoBot_II_BT_Command_V2.apk (Executable file generated by MIT Inventor that can be installed in any Android Device).