Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.
Cellcrypt - Cellcrypt app provides features so you can enjoy secure conference calling, messaging, and sharing of documents.
Enigmail - Security extension to Mozilla Thunderbird and SeaMonkey
WAMR - WAMR – Recover Deleted Messages and Status Download is a powerful app that helps you recover text messages and media attachments.
Easy Message - Easy Message app comes up with features to help users in effortlessly sending text messages to a phone number, which is not in the contact list.
WhatsRemoved+ - WhatsRemoved+ is a mobile tool developed and published by Development Color for Android devices only.