On Android you can use RedPhone for secure calls and TextSecure for secure text messages. These calls and text messages are compatible with calls and text messages in Signal iOS. Someday TextSecure and RedPhone on Android will be integrated into one unified product called Signal.
The TextSecure brand is unfortunately dead to me. Although I liked the idea in theory of the SMS backwards compatibilty layer, in practice it confused people and caused technical problems which stopped many of my friends using it.
With a reboot as a product with the new name Signal, I can market it again. Needs an Android version first though!
I agreed to that from the first day I used it. It's strange that the developers themselves don't realize it. Just kill SMS support. Nobody needs it anymore. I mean for crying out loud, data-only apps such as BBM and Whatsapp became most popular in poor countries, so I don't think the "but not everyone has money for data" argument works anymore.
I disagree. Most of my contact list doesn't use TextSecure/Signal; when I want to send someone a message I don't want to have remember if they use textsecure in order to open the optimal app for messaging them with. Maybe I'd even first open textsecure, then be disappointed that they're not in there and have to open the plain sms app. How annoying that would be.
Nobody needs SMS if everyone could just use the same app. But my brother uses a dumbphone and my mother uses an iPhone with nothing but iMessage and I use an Android and don't really feel like installing whatsapp or whatever the latest fad is just because one or two of my friends has it. Over SMS I can communicate with them all, and if any of them ever install textsecure I get encryption as a bonus.
They're planning to drop support for encrypted SMS fallback (a decision I have mixed feelings about), but plain SMS functionality will remain in the Android client for the forseeable future.
On Android you can use RedPhone for secure calls and TextSecure for secure text messages. These calls and text messages are compatible with calls and text messages in Signal iOS. Someday TextSecure and RedPhone on Android will be integrated into one unified product called Signal.