Telegram iOS app: In the “Chats” tab, click the new message icon in the right upper corner. Select “New Channel.” The optimal dimension of the avatar on Telegram is 512px by 512px, and it’s recommended to use PNG format to deliver an unpixelated avatar. To upload a logo, click the Menu icon and select “Manage Channel.” In a new window, hit the Camera icon. 2How to set up a Telegram channel? (A step-by-step tutorial)
from us