I did see the other questions about implementing trial apps (meaning apps that expire after being used for a certain time). They said the only real way to do it is to set up your own server and use some unique device ID to check if users have finished their trial. I don't know the first thing about setting up a server nor do I have the money for it.
I'm curious if it's possible to just use Firebase authentication but instead of users manually logging in they get automatically logged in using their unique device ID, and then their install date is checked using Firebase? Is that possible?