Mike’s app melds Apple iOS stuff with an Arduino:
I wrote an iOS app find my Arduino over Bonjour and talk to it. It’s call Ciao, and the App Store approved it last Thursday.
Ciao makes it easy to talk to your Arduino from your iOS device. Load one of the example sketches onto your Arduino, and Ciao will automatically find it over Bonjour. You can use Ciao to control your Arduino or get live information from your Arduino.
Via the contact form.