You need a phone number that can receive texts for the initial setup, but once you're set up people can add you by @username and never need your number. Stuff like https://www.textnow.com/downloads works just fine for the initial text. Once you have a single device set up, it messages your existing devices rather than sending SMS when you try to connect another device.
One of the main people behind Signal actually tried to spread a bunch of FUD about Telegram years ago, saying the crypto was weak, but it's really not. No working POC code was provided to decrypt anything, just FUD.
Telegram isn't remotely similar to Signal. Telegram communications aren't encrypted by default, and Telegram group chat messages aren't encrypted at all.
To say there's no encryption AT ALL when it's fully encrypted over the wire is still false. Not having E2E encryption is different than not having encryption AT ALL.
All crypto is weak until proven otherwise. Telegram never received a good review from cryptographers. The fact that no POC was provided may just as well mean no cryptographer cares enough to find a bug.
No, he said the crypto was weird (which it is. Who the eff uses IGE mode?) and that their competition to find vulnerabilities was bullshit and would be secure even using crypto primitives that are known to be weak.
You need a phone number that can receive texts for the initial setup, but once you're set up people can add you by @username and never need your number. Stuff like https://www.textnow.com/downloads works just fine for the initial text. Once you have a single device set up, it messages your existing devices rather than sending SMS when you try to connect another device.
One of the main people behind Signal actually tried to spread a bunch of FUD about Telegram years ago, saying the crypto was weak, but it's really not. No working POC code was provided to decrypt anything, just FUD.
Protocol details here: https://core.telegram.org/mtproto They just released MTProto2 in the last year.