Encrypted chat and call app Signal is coming to Android six months after it was first released on iOS. Developer Open Whisper Systems is rolling together two of its existing apps — TextSecure and RedPhone — over the coming days, combining the former's text chat capabilities with the latter's calling functions in one new app. As with the iOS version, any text, video, or image coming from the Android version of Signal is encrypted before it leaves your phone, meaning that Open Whisper can't see what you're sending.

RedPhone users will be prompted to download the new Signal app, while TextSecure users will simply need to install an update that keeps the same private chat capabilities as the previous app, also adding RedPhone's ability to make and receive secure calls. Users can communicate using their existing phone number and address book, rather than needing to set up a separate login, and the Open Whisper team promises all conversations and messages sent between devices running the app are end-to-end encrypted.

I use Signal every day. #notesforFBI (Spoiler: they already know) https://t.co/KNy0xppsN0 — Edward Snowden (@Snowden) November 2, 2015

The new app means that Android and iOS users will be able to send encrypted messages back and forth to each other across the OS divide using Signal, although a promised desktop app has yet to materialize. Open Whisper's code has been adopted by software as huge as WhatsApp, but if you're still not convinced the app is secure, then you're free to dig around in its code to find security holes — the whole project is open-source. You can probably trust it anyway, as the Android version of Signal has already got the seal of approval from the poster child of encrypted communication, Edward Snowden.