The Realme notification bar displays HD 1. What does that mean?

HD call function is a voice service, which can shorten the waiting time of 4G users and improve the call quality. At the same time, it can provide high-speed video calls and multimedia services. Both parties need the mobile phone card of China Mobile, because only China Mobile has this service at present.

High-definition voice service, like making phone calls and sending text messages, is a free basic service function that mobile phone numbers automatically enjoy, and there is no function fee. It is a brand-new voice service launched by China Mobile's 4G brand. Its core is relying on the high-speed 4G network, using the new VoLTE technology to achieve high-definition voice and video calls, bringing a clearer and new communication experience without delay.