Use this recipe when you always want to play music from a certain music app. When this recipe runs it will ask you only the first time complete task using which app that's when you select your choice of music app.
If
Connects to a Bluetooth device
This Trigger fires every time your Android device connects to a Bluetooth device.
Then
Play music
This Action will play music on your Android device. The music played depends on your device and setup. Depending on your version of Android, playback may not start automatically.
Explore more great ways to automate Android Device and Android Device