This comes straight from Kryptos’s own GitHub page — it’s free. Need help installing?
What it looks like
About this app
Kryptos lets you encrypt messages without ever leaving the messaging app you're already using. It works as a keyboard: type your message, it encrypts it, and the other person's screen decrypts it back, so there's no separate app to jump into.
It uses the Signal Protocol for strong end-to-end encryption and works completely offline. Kryptos is available for both Android and iOS.
From the app’s home page
- See the codeHow it’s made — every line is public
- WebsiteThe app’s own home page
- Questions & commentsTalk with the people who make it
- Report a problemTell the makers something is broken
- All versionsOlder downloads and what changed
- LicenseThe rules for using and sharing it
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