Today's update adds 
Voice Chats, creating a seamless integration of text and talk in groups. Members can join and leave these 
open conference calls at any time for a bit of spontaneous conversation alongside their usual text messages and media.
As the calendar turns over to 
2021, we'll be busy taking in your feedback and improving Voice Chats with features like 
video and 
screen sharing at the top of our list.
To read about all the features in this update, like 
SD Card Storage for Android and more, check out the full post on our blog:
https://telegram.org/blog/voice-chats