Does T Mobile Use Gsm. Voice and data services dont work at the same time when on 2G. While 5G access wont.

Now that T-Mobile and Sprint have joined forces were delivering on our promise to use 5G for good. Does Xfinity Mobile use GSM or CDMA. Free unlimited service for first responder agencies.
The phone wont even work with ATT Verizon or Sprint.
Our maps show coverage provided by T-Mobile in the US. January 1 2022 Sprints CDMA 3G. The T-Mobile network uses GSM network standards and its not a CDMA network. It also gives those with 5G-capable phones access to T-Mobile.
