Looking for a secure way to make calls and send messages on Android phones? Signal might be the app you want — and considering Edward Snowden gives it his official blessing, you can probably count on its efficacy.
Signal is actually just a new name for an app combining the functions of TextSecure and Redphone, both from Open Whisper Systems. TextSecure let you message freely and privately with others using the app, and Redphone did the same for phone calls — but now you'll be able to do both from within Signal. It came out for iOS earlier this year, and was just on Monday released for Android.
You don't need to sign up with a username or password, and there are no ads or anything. Just download it and when you reach out to someone on your contact list, if they have Signal as well you will be connected securely.
Alternatives like Whatsapp and iMessage also offer end-to-end encryption, but they don't carry the recommendation of one of the most wanted men in intelligence.