Sale has ended but you can still get this app.
Download Crypto SmS Now

Official Description

Send Encrypted SMS & Decrypt Received SMS.
With Home made Algorithme available here : http://encrypt.dyrk.org/
Use the standard protocole to send sms, no data stored. Send Encrypted SMS & Decrypt Received SMS.
With Home made Algorithm disponible ici: http://encrypt.dyrk.org/
Use the standard protocol to send sms, no STORED DATA.