Seald - Keep your conversations secure, everywhere.
NetSfere Secure Messaging - NetSfere Secure Messaging is a secure messaging app that enables you to send messages by using 256-bit device-to-device encryption features.
Spike - Spike solves businesses' communication chaos by bringing together email, team chat, collaborative docs, and meetings, into one feed.
PhoneLeash: SMS/MMS forwarding - PhoneLeash: SMS/MMS forwarding app offers features that let you forward your desired text messages and multimedia messages to your email or your other mobile phone so that you can access them later.
Keybase Chat - End-to-end encrypted chat built into Keybase
Cellcrypt - Cellcrypt app provides features so you can enjoy secure conference calling, messaging, and sharing of documents.