Oversec

Oversec is an open-source Android application in the Security & Privacy category. It encrypts and decrypts text across apps without requiring the underlying app to provide its own encryption support. It is intended for people who want to exchange private chat or email messages or keep encrypted notes on their phone.

Oversec works with chat applications such as WhatsApp, Line, Snapchat, Instagram, and other chat apps. It also supports sending and receiving PGP-encrypted messages through Gmail or another email application. For outgoing text, it reads content from an active input field, encrypts it, and places the encrypted result back into that field so it can be sent through the surrounding app. For incoming encrypted text, it monitors the screen and displays the decrypted version as an overlay in place of the encrypted text.

The application is designed so that clear text is decrypted only while it is shown on the screen. It does not persist the clear text, so it is not stored in the file system or accidentally included in cloud backups. Oversec can encode encrypted messages using invisible zero-width characters and can add decoy text after them, allowing the encrypted content to be carried within text that appears ordinary. It does not require internet access, which keeps decrypted information from leaving the device through the application.

MirrorNest distributes the official Android build directly from its own storage. The build is scanned for malware before it is published in the catalog. This distribution fits Oversec's Android and Security & Privacy classification while giving users access to an open-source application through a mirrored download source.