Secret messages is a secret message application hidden behind a basic game (named Apple Rush)
It does not deal with secret SMS but with secret (free) messages, outside the SMS system.
You want to talk with your girlfriend with no trouble with your wife ?
You are looking for a very confidential messaging system, who wont appear in any journal ?
Run Apple Rush, and start playing.
Inside the game screen, quickly click on the top right corner, then on the top left corner, then on the bottom right corner, to access the secret messaging screen.
Create a conversation that your girlfriend will join, and send as much free messages as you want (WiFi or 3G access needed).
You can quit and recreate conversations as much as you want.
Only 2 persons can participate a conversation, your conversation cannot be joined by a third person.
Your wife (or husband) can search for hours before finding anything compriming in your phone...