телеграмм X уже не обновляется, и там не будет новых фич

Please note that Telegram X for iOS has been discontinued. Its code has been merged with the main Telegram app. Please download it from the AppStore to get access to new updates: https://itunes.apple.com/app/telegram-messenger/id686449807

The main Telegram app has all the features of this app – and more, including Archived chats. It also supports multiple accounts (Settings > Edit > Add Account).

Thank you for helping us test and develop Telegram X.

Насчёт X для андроид не знаю - им не пользовался