[Android Central Question]

Using a unlocked galaxy s8 on tmobile network trying to see how to activate hd calling so I can use the internet while on the phone

[anon(123856)]

You may not be able to do that without installing a T-Mobile rom. On my unlocked S8 on Verizon the only option I have is VoLTE.

[James Rogers2]

You can't activate HD calling using a Verizon phone on T-Mobile. But you should still be able to use the phone and internet at the same time. I had a a Verizon Note 8 on T-Mobile and could do it. The 4G signal will drop to 3G when you're using the phone, but you still should be able to use the internet. The only other way is to change your phones firmware to T-Mobile.

https://forum.xda-developers.com/sho...70&postcount=3