blabber.im is a fork of Conversations with some changes, to improve usability.

Connection security and the protection of personal data are very important for
us, so we enforce encrypted connections between messenger and server, making it
almost impossible to intercept and read your messages by strangers.
If that's not enough for you, end-to-end message encryption such as OMEMO
or OpenPGP can be used. This allows messages to be encrypted on the sending
device and decrypted only by the receiving