But you do need a phone number to setup Telegram. I like the fact that it allows not having to share one's number with others by setting a username and sharing that instead (though setting a username increases the chances of getting spam/unsolicited messages especially if your profile pic looks like a human female and your name sounds like one too).

Wire [1] on the other hand, doesn't need a phone number and can work with an email address.

[1]: https://wire.com