Want to show your love, thankfulness, or just kidding somebody, in a surprisingly way? Hey iWannaSay will help you.
A quick tour video: http://youtu.be/0NkJWHDaP0Y
Create colorful message in your iPhone and show it on others is just a simple 1-2-3, with beautiful themes:
1) Create message on your phone and remember the token
2) Open iwannasay.us on your target phone and input the token
3) Add to Home Screen and its done