Anonymity is not the only reason for usernames though: People sometimes switch phone numbers, and some switch them more often than others (exchange/phd students

Anonymity is not the only reason for usernames though: People sometimes switch phone numbers, and some switch them more often than others (exchange/phd students going to different countries/, moving to different countries for new jobs etc). Re: Wire, I tried it back when it had video chat (one of the few options between iPhone and Android) and Signal didn't. But I found Wire to be too unstable to be really usable. That is to say, my family members quickly got annoyed and demanded I buy an iPhone. Signal video chat solved that issue :-)