Cellcrypt - Cellcrypt app provides features so you can enjoy secure conference calling, messaging, and sharing of documents.
WAMR - WAMR – Recover Deleted Messages and Status Download is a powerful app that helps you recover text messages and media attachments.
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.
WhatsRemoved+ - WhatsRemoved+ is a mobile tool developed and published by Development Color for Android devices only.
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.
Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.