Filesystem:/Applications/Compass.app

iOS refers to the compass internally as the magnetometer. It exists in all iPhones since the iPhone 3GS and all iPad models except the first-generation iPad. The compass found in the iPhone 3GS is the AKM Semiconductor AKM8973, whereas the iPhone 4 and iPad 2 use the AKM Semiconductor AKM8975, the others' are not confirmed.