@NatureMCPetra van Cronenburg 
@maggiejkMaggie Maybe 
@johncarlosbaez 
@ppdelftPiratenpartij Delft
Even got my mom over on Signal, for whom the internet is one big mystery she doesn't (want to) understand.
And she is using it, no problems (except some UI shortcomings when a call is made and the phone is locked).
@smallcirclesjust small circles 🕊 @NatureMCPetra van Cronenburg @maggiejkMaggie Maybe @johncarlosbaez
On Android, make sure this permission is on so incoming calls are shown on the lock screen:
Settings / Apps / Signal / Notifications / (scroll down) "Allow full-screen notification"
Without this permission, the phone will ring, but you won't see anything on the screen when it is locked, so you would first need to unlock before you can answer/reject a call.
If you have a fediverse account, you can quote this note from your own instance. Search https://mastodon.pirateparty.be/users/ppdelft/statuses/114437614791453222 on your instance and quote it. (Note that quoting is not supported in Mastodon.)