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.
Slack - A messaging app for teams who see through the Earth!
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.
Foxo - Health industry's most powerful secure messaging platform
Reach - Mass messaging app for the iPhone
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.