Android: When CyanogenMod announced that it would be rolling encrypted text messaging into its ROM, we were a bit disappointed that it would only work for CM users. TextSecure thankfully broadens the base, making encryption available to any Android user.
The app is the same one that CyanogenMod has based its implementation on. TextSecure will always encrypt your messages locally. However, if you're texting someone using the same TextSecure system (which now includes all TextSecure-supported CyanogenMod users), your messages will also be encrypted in transit, so you don't have to root and ROM your phone to improve your messaging security.