Youll need a number transfer PIN for this You may find it easier to activate your T-Mobile SIM card on your computer as ...

If you have one of the compatible Metro by T-Mobile Android ... need to buy a SIM card kit. When you get the SIM card, insert it into the tray on your device and activate it.

but none of them involve bringing a new device to T-Mobile. For example, if you want to swap out your SIM card or add a DIGITS Talk & Text line, you will not have to pay the activation fee.