On some website (http://ad1.ru/) I had seen possible get personal notify eq :(offer, ticket, discound) on telegram. I can to add only mobile phone (+7 906 247 00 01) in my contact list telegram and all. How they did it?
I read telegram api documention and I found nothing. also I found this question How to obtain Telegram chat_id for a specific user?
wherein said that before send message I can get chat_id and send message boot telegram for get user chat_id from message