Q: has anyone ever bought a sidekick from a t-mobile phone then used it with at&t? i was going to do this but i figured i would ask first.
A: You can use any GSM phone on any network as long as it is what is know as "unlocked". Check with the seller to make sure the Sidekick you are going to buy is unlocked. Att was good about unlocking my phone when I called customer service. Some carriers won't do it, and some charge for it, as high as $50. Check with the place you are purchasing from to see if your Sidekick comes unlocked or if they will unlock it for you after it arrives either over the phone or at a store. I know Motorola will sell their phones unlocked from their website....