Threema Alternatives for Android

Telegram is a free cloud-based instant messaging platform.

WhatsApp Messenger is an instant messaging platform owned by Facebook.

Slack is a cloud-based team collaboration tool.

Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption.

Signal is the most scalable encryption tool.

Wire is a cross-platform, encrypted instant messaging client created by Wire Swiss. It is available for iOS, Android, Linux, Windows, macOS and Web browser clients.

ChatSecure is a messaging application for iOS which allows OTR and OMEMO encryption for the XMPP protocol.

Xabber (XMPP and Jabber) is a XMPP client for the Android Operating System.

Sicher is a freeware instant messaging application for iOS, Android, and Windows Phone. Sicher allows users to exchange end-to-end encrypted text messages, media files and documents in both private and group chats.

Zulip is a chat and collaborative software.

Disa is your new messaging hub. Conversations from different services can seamlessly be joined together, or disbanded within seconds.

Wickr is an instant messenger application.

Dasher Messenger provids a way to message friends.