And what is wrong with the Telegram? Quite safe messenger. And absolutely free.
Doesn't it need your phone number? What about server part?
But if other users doesn't know your number, say like you're in a group discussion or a bitcointalk telegram bounty (lol), it won't show. I also heard some ico devs prefer to use discord as they are even more safe (they said) although I hadn't privileged myself on trying them. This is why I wanted to know about this claime-to-be more secure too. Dev said to see comparison table, but I can't find the table on his images.