Crypto Message System is a mobile client to send secure SMS. Set the password and compose the message, it will be encrypted before sending. It is possible to set a different password for each private message.
Secure messaging is used in many business areas with company-wide and sensitive data exchanges. Financial institutions, insurance companies, public services, health organizations and service providers rely on the protection by Secure Messaging.
The free version contains banner ads.
For Donut/Eclair users: this app requires Android 2.2
(Froyo)