In addition to packing an AGPS, the N97 also boats of a digital compass which helps point you to true north while using Ovi Maps (Nokia Maps). What Nokia did not put inside was an independent application for the compass itself, therefore you could only use it with Nokia Maps till now. However, TongRen has come up with a light weight compass application that helps the phone act as a compass independent of Ovi Maps.

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The Missing Compass Application For The N97 Is Here