The Motorola 815 comes packaged with a phone holder, visor clip, dash mount, car charger, and the MOTONAV service pre-installed on a memory card.

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The battery can also be re-charged from a wall or car charger.

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They should also remember to bring along a GPS-equipped smartphone (and its car charger) to help them find their way across this massive city.

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For many juice-strapped motorists, the TYLT Band Car Charger is the answer to their prayers.

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The Motorola T805 comes with a car charger, cell phone mount, dash mount and visor clip -- with a requirement for a 12-month MOTONAV national subscription (including up-to-date maps).

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But, if you're not lucky enough to have access to one of those, the Model S will be quite happy to pull juice from a standard Level 2 charger -- and, should you opt for a second, the car can top up again in half the time.

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On the road: Optional City Navigator mapping provides detailed street maps, millions of preloaded points of interest and onscreen turn-by-turn directions to your destination, and an optional Auto Nav kit adds a suction mount and car charger.

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