One of the biggest issues that still plague phones and navigation devices that are equipped with GPS chips is indoor reception. Go under a bridge, or inside a tunnel, or inside of a building, and you'll probably have a hard time keeping a decent reception lock. It's a frustrating experience, and now that phones are being used more and more as true navigation devices, it's a growing problem that really needs a solution. Skyhook Wireless has been working on this for awhile now, with their Core Location Platform
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