uninstall

Hi everyone.. i've a big problem, i must know if a user has uninstalled the app. I use firebase messaging to send push notification using a token. There is a way to know if a user has deleted the app? I read that maybe using the fact that the firebase token became invalid after a while... but i...

I have a database file located on dirinternal, on b4a 5.02 after uninstall, this file was always deleted but in b4a 8 this file remains in some devices, it is removed only when I clean app data. Is there something that I should do to remove this file on uninstall without change my app folder...