Hiroyasu POC network radio

I have this POC radio with Android 5.11 and its born with zello software but i like to use se.lublin.mumla_101.apk but the device only have a setting and zello that it starts up as default but I have installed mumble using adb install and to start mumla using adb shell monkey -p se.lublin.mumla -c android.intent.category.LAUNCHER 1

I am not sure if this is the correct way but using srccpy the device only have very small screen not like normal android devices so I use mw size 240x200 and to setup the PTT key for speaking - and it works fine with mumla but pressing a wrong key it jumps to zello - but I would like the poc radio to start mumble as default and not the zello app but the possible hardcod launcer only provide me with zello and setting so any recommeded solution ? I am not so used to playing with android but making the POC radio run mumla is cool as a lot network radio.

This poc radio is available under alot names.