iOS: Anyone can pick up your phone and read your text messages. It's also not that difficult for someone to install spy software. If you want to keep your messages private, Black SMS is an app that provides a very simple method for doing so.
You simply type in the message, set a password, and send it over to iMessage. The recipient can then use their copy of Black SMS to decrypt the message using the password you set by simply pasting the message into the app and entering the password. (Watch the video above for a demonstration.)
This is a very helpful tool when you're exchanging sensitive data over SMS. You probably won't feel the need to use it for every single text message you use, as the process is a little bit tedious for quick, everyday communication. Nonetheless, when you've got something private to share, Black SMS can help you keep it that way.
Note: A free decrypt-only version of Black SMS will be available soon, but for now you can get the regular version for $0.99.
Black SMS ($0.99) [iTunes App Store]