Spike - Spike solves businesses' communication chaos by bringing together email, team chat, collaborative docs, and meetings, into one feed.

Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.

ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.

StealthChat - StealthChat is Encrypted, Private, Secure Calls and Chats on Android and Apple iOS

Seald - Keep your conversations secure, everywhere.

Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.