UBM TechInsights' detailed teardown of the iPhone reveals a slot housing a micro-electro-mechanical gyroscope. The device is absent from the iPad -- but there's an open slot for it.
The integrated circuit marked "AGD1 2022 FK9AH" is a 4 by 4 mm, micro-electromechanical (MEMS) gyroscope. It's situated on the iPhone 4's main circuit board.
See main story, iPhone 4 Teardown Telegraphs Future iPad Gyro.
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