For e2e encrypted chat there's https://conversations.im https://conversations.im. I've been using it for a while since it lets me bring my own domain and have b

For e2e encrypted chat there's https://conversations.im https://conversations.im. I've been using it for a while since it lets me bring my own domain and have been very happy. The Android client supports encryption with PGP keys and OMEMO (a double ratchet like Signal uses with some nice key trust options added on top to make it easy for novices, but configurable by experts).