How iPhone 3G S Compass Works

How iPhone 3G S Compass Works

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Apple Iphone 3G S uses a magnetometer developed by Asahi Kasei. AK8973 is a small chip sensor that listen for ultra low frequency from a specific spots, like North.

For more information about how Compass works you can read this datasheet information http://bit.ly/AK8973

By time to time you need to re-calibrate compass, here is how http://bit.ly/calibratecompass