How Is This Better/Different Than GPS?

A GPS/Cellular based device can only operate when there is cell phone service and a clear view of the sky for reception from the GPS satellites. GPS reception also requires a great deal of power to operate, necessitating frequent (sometimes daily) battery charging. MarcoPolo does not require any of these external services to operate, so it can work anywhere. And without relying on GPS, MarcoPolo’s tag battery lasts up to three months on a single charge.
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