Phones now have a feature called Voice over LTE (VoLTE). This lets you make calls using the LTE signal instead of the older 3G signal.

Benefits of VoLTE:

• Better call clarity
• Use data while on a call
• Connect calls faster

Another benefit is that your call won't drop if you leave a Wi-Fi area, as long as you have Wi-Fi Calling enabled. Before, if you started a call on Wi-Fi, it would drop when you left the Wi-Fi area. Now, VoLTE uses the cell network's data signal to keep the call going.