Keeping TR running in background (Android)

So during a workout I am running TR app and Spotify at the same time on my Android phone, but I don’t need to look at the TR app because my workout profile is also displayed on my PC laptop in front of me - running Golden Cheetah in Train mode. Running TR on the phone allows redundancy in recording and send a nice TR graphic to Strava afterwards. So ideally I would like to keep TR running in the background and have Spotify in the foreground switching music as I like. The problem is TR stops the workout in the background.

Does anyone know how to keep the workout going?

Thanks

LtS