Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.
WAMR - WAMR – Recover Deleted Messages and Status Download is a powerful app that helps you recover text messages and media attachments.
Enigmail - Security extension to Mozilla Thunderbird and SeaMonkey
Cellcrypt - Cellcrypt app provides features so you can enjoy secure conference calling, messaging, and sharing of documents.
Ciphermail for Android - CipherMail for Android is an Android application which can be used with your existing Android mail...
WhatsRemoved+ - WhatsRemoved+ is a mobile tool developed and published by Development Color for Android devices only.