WhatsApp, Telegram, Signal, Matrix.org, Privnote, CSipSimple, Tox, Briar, Zulip, Keybase, RetroShare, SafeNote, Zyptonite, Lumicall, Cipha, Gryphn Secure Text Messaging, Comfi App, Anywhere SMS, BloomText, HWIZIT, Cashew Secure Messenger, CHARE, GizliNot, Siphon SIP are some alternatives to Adamant Messenger.