In order to promote the use of its VoLTE function, China Unicom recently sent reminder text messages to its iPhone users.
China Unicom said that users only needs to upgrade iOS 13.3 and turn on 4G high-definition calling (VoLTE) in the settings to enjoy better experiences.
On December 11, Apple pushed iOS 13.3 updates to iPhone users, and then China Unicom pushed operator updates to Apple iPhone users and and officially bring VoLTE capabilities to iPhones.
Users can go to System-Settings-Cellular Network-Cellular Data Options-Voice and Data to choose 4G and VoLTE.
VOLTE stands for Voice over Long-Term Evolution, which means a high-speed wireless communication standard for mobile phones and data terminals.
VoLTE is one of the main technologies of 4G networks. Its main advantage is that when users make calls on 4G networks, the network will not fall back to 2G or 3G, and it will not affect users' current network experience.
For example, if a user is playing a mobile game or downloading something, a call comes in, and without VoLTE, the network fall will have an impact.
