OK, just got an old S3. Sprint version. Upgraded it all the way to Stagefright fix/KitKat 4.4.2. Not activated as I'm on Virgin Mobile USA. Not sure if it's prepaid or contract version. 1. Is it possible to activate on VM without rooting, and installing custom recovery and ROM? If not I'll use it as a WiFi device for games, streaming to tv, fm radio and as a mini tablet. 2. If I use a 64 GB card reformatted to fat32, will that work on the S3? Thanks for any advice.