florinc : yes, there is a serial port, but the official SDK won't let you access it, so you'll have to use a jailbroken iPhone / iPod to use it.
Using the new External Accessory framework, your application can now communicate with "Made for iPod" hardware accessories attached to iPhone or iPod touch through either the 30-pin dock connector or wirelessly using Bluetooth.
I know I'd like to have my Touch and Arduino talking without jailbreaking.
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