and all iPhone models, even though they use the same plug, are incompatible with each other’s docks because of artificial incompatibilities created by a series

and all iPhone models, even though they use the same plug, are incompatible with each other’s docks because of artificial incompatibilities created by a series of resistor codes hidden inside the cable or device. Good story but not actually true. (does it matter on the Internet anymore?) The iPhone 4 works in the iPhone 2G dock. The iPhone 3G works in the iPad dock (by the looks of it the iPhone 4 will also) Audio out is a different issue since Apple has changed the way the dock connector outputs audio on the iPhone for integration with car audio systems to reduce GSM interference. That being said I don't know of any other SmartPhone that comes with a dock these days so it's a bit of a moot point anyway. If you want a dock Apple will sell you one.