Seald - Keep your conversations secure, everywhere.
ChatSecure - ChatSecure is a free and open source messaging app that features OTR encryption over XMPP.
Spike - Spike solves businesses' communication chaos by bringing together email, team chat, collaborative docs, and meetings, into one feed.
Chatib - Chatib is an online chat room where you can meet and chat with new people, make them friends, or even data them online.
Keybase Chat - End-to-end encrypted chat built into Keybase
Qudo – Find Snapchat Friends - Qudo is a great app that helps you Find Snapchat Friends directly from your iPhone.