Handcent - Handcent – Free Messenger for Texting and MMS is the most customizable, powerful, and next-generation messenger app that makes user-experience more enjoyable and convenient.
Wickr - Wickr is a free end-to-end encrypted text, video, picture and voice messenger with full sender...
Reach - Mass messaging app for the iPhone
Confide - On the off chance that you need to get your messages private and encoded then utilize Confide that will fill in as your own and classified courier.
Bleep - Bleep is an insured and secure messaging application by the Bit Torrent that you can use for valuing the private and safe communications.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.