Telegram.me, Changing Numbers and PFS
Opening a telegram.me/YourUsername link on your phone will now automatically fire up your Telegram app and open a chat with that user. You can share username links with friends, write them on business cards or put them up on your website.
Changing Your Phone Number
It is easy to switch to Telegram and retain your social graph, since it is based on phone numbers. But what if you need to change the phone number itself? As of today, you can change your number in Telegram — and keep everything, including all your contacts, messages and media from the Telegram cloud, as well as all your secret chats
Your mutual contacts (people in your contacts, who also have your number) will get your new number added to your contact in their address book unless you have blocked them in Telegram. This makes changing numbers even easier.
Perfect Forward Secrecy
Last but not least, Telegram’s Secret Chats now support Perfect Forward Secrecy. What this means is that your Secret Chats will now automatically change encryption keys after a period of time, in order to keep past communications safe. This way you no longer need to manually re-create Secret Chats to achieve this level of security.