Let's say they implement this. What are some ways around it? You could uninstall Facebook and say you don't have an account. You could sign out of your Google account (Android). I wonder if there is a way to programmatically back up your contacts, remove everything, the reimport them.

I happen to be a US cit, but if I wasn't, I would just factory reset my phone before entry. Periodic factory resets seem to be a good idea anyway.