I have been looking into preserving user data, should users delete our app, and then decide to reinstall. So I have a couple questions related to this that I'm having trouble finding answers to. We are already storing all data on our server, but want to make sure that there is a safe way to make sure we are getting the data for the correct account. (We can currently do this on other devices by using google play accounts, and users can save their account via facebook login on amazon, but we don't want to enforce people to need a facebook account)
1. Is there a way to preserve any data on device when our app is uninstalled? (e.g. using SharedPreferences)
2. Is there a unique user id available for the current, logged in, user? Or does this require hooking up amazon login?