You can use the classical Bluetooth adapter for Arduino Like HC-06, HC-05 or HC-07 in joint with any type of Arduino Board. You can Download Sample Arduino Program by Using Fab button which is present in downside or by Navigation Menu.
This app will Send Integer Data in the form of String formate by affixing "a " on last. For Example, if you press L1 in Home Screen, It will send String "401a" to switch on and "402a" for switch off also. For the more detailed program, Download program from App.