Today I got a Lumia 635 on Virgin Mobile and I want to sell my old F3. It is rooted on V7. How do I return it to stock before selling it? I'm a little leery about doing a factory reset. When my SD card died, I had some System apps linked to it via Links2SD. Those apps are now gone. For this reason, I'm concerned that if I do a factory reset it will brick the phone. I do have a nandroid back I made before upgrading to V7. Should I restore that then do the factory reset? Or is the missing system apps not a problem?