As VoLTE is an enhanced 4G feature, you must be in a location with 4G network quality. You must ensure you and the person you are calling have the following:
- 4G SIM (skitto SIM are already 4G SIMs)
- VoLTE enabled handset with the option turned on
- updated OS software of your phone
If you have the above, your handset should show 4G with HD/VoLTE icon on the top bar of the screen which indicates you are ready to experience VoLTE calls.
Do note, for iPhones it will always show 4G. But during a VoLTE call, the network bar indicator will remain 4G instead of 3G indicating that you are on VoLTE calls