Shtuff Chat - Free Group / Team chat with persistent history.
Discord History Tracker - Discord History Tracker is a great tool that enables you to select chat history and save it in your private conversations, servers, groups, and then view it anytime without needing an internet connection.
Anologue - Disposable online chat.
Pyno - Pyno is a mobile application that shows your Facebook chat history.
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
AirMessage - Use iMessage on any Android phone 💬