X-Crypt PRO

If you are tired of deleting or hiding your messages, X-Crypt is the perfect
answer for you! The best Android application for encrypting and decrypting your text messages! No more heart attacks when your girlfriend/boyfriend uses your phone, no more fear when you accidentally leave your phone unsupervised at your work, classroom, room etc. Feel secure when texting about your personal stuff, or cheating on a test.

Easy to use with no copy/paste required, open your message application with encrypted text already inside directly from X-Crypt. App also waits for incoming encrypted texts and gives you notification if that happens so you can, via notification, open app with encrypted text you just received already inside ready for decoding.
Encrypting uses your 4 number password you type when you finish writing your text so there is no way anyone can break it unless they know your "key". Of course person that is receiving your texts must use the same key to decrypt it which means you just created canal of communicating only the two of you can understand.