How to avoid session dieing when exiting infected app

I'm trying to get into the world of android-cybersecurity. I've programmed my first payload with msf venom and put it into an apk of an app I've developed. After exploiting in metasploit I can say that It'works, but It's far from being at least useful. When I closed my application the meterpreter session dies (and I can understand the causes) but I'm here to ask if anyone can explain how can I avoid this disconnection when I exit the app. Unfortunately I don't have any ideas and like I said I'm new to cybersecurity (But not to android programming) so when you'll try to explain try also to be as clear as possible. Thanks for any help you can give me :)