You can now set a self-destruct timer for any photos and videos you share in private chats. If you set a timer, the countdown starts the moment your recipient opens the photo or video you sent. After the time runs out, the photo/video will disappear forever, just like in Secret Chats.
Telegram checks photos & videos to see whether they are publicly-available ones …
If they are, and they are already cached by the service, it serves the cached version from a content delivery network. This significantly speeds up downloads, while retaining encryption. Caching applies to groups with at least 100,000 members, and the company wrote a blog post explaining how it works.
While these caching nodes are only used to temporarily store public media (imagine Telegram versions of superpopular YouTube hits), all data that goes through them is encrypted with a key unknown to the caching nodes. In other words, we treat these CDN caching nodes just like we treat your internet provider – they only ever get encrypted junk they can’t decipher.
The app also allows you to add a short bio to your profile, which is accessible to users in groups you’ve joined. Finally, the latest update also lets you see more stickers at once.
Telegram Messenger is a free download from Google Play.