I have created two app inventor apps to connect with micro:bit (one is published on Google play). The one not publsihed I have some strange problems with. It is in fact a version taken from mit app inventor example app. I pair, and after that I open the app. I select scan, then stop scan. So I select the microbit I want to connect to and then I press connect. On the micro.bit I have a code that will play a melody when the connection is OK. The melody plays, but then the app close. if I start the other app (lets say app nr 2), it will connect fine. If I, after connecting with the other app (app 2), then the first will work. I find this a bit strange.
Or, what is the difference in the connection procedure between the two apps (show some blocks). And, what is on the micro:bit? Upload the .hex file maybe?
Does it say no pairing required?
And, what are the versions of the BLE extension and the micro:bit extensions in both apps?