Hi Herman
To support iPhone device features, Tersus uses the capabilities of the Safari browser ("Mobile Safari" - the version that runs on iPhone).
This is made by running simple Javascript that activates the required device feature.
For example, for Getting the iPhone orientation, use the following model:
You can see it in action in our Memory Game example (http://memorygame.tersus.com/) - try running the game on your iPhone and you will notice the game won't start unless iPhone is in landscape mode.
For other features, use the 'Run Javascript' plugin of Tersus in the same manner.
Note that Mobile Safari has recently added support for some new features like GPS (Geolocation), available starting with iPhone OS 3.0.
Danny