Glass knows the weather, too, defaulting to your current location, but letting you ask about other places, too.

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Uses nearby WiFi access points and GSM towers (on the iPhone, anyway) to roughly guesstimate your current location.

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Your current location in the book in displayed in the lower left-hand corner.

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Ideally, the app will automatically start from your current location.

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In private chat, you can share your current location, pin-mapped.

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Once you get going POIs can be searched near your current location or on the current route and, if you find something, it can be easily added as a via point.

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Next to each address book entry is an icon that when selected will cause the unit to draw a map from your current location to the address given in the address book.

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You may have noticed Google's forecast feature on your HTML5-capable smartphone browser -- simply typing "weather" into the search field brings up a basic real-time temperature tool, complete with hourly and five-day forecasts for your current location.

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In the lower left is a button that brings up your current location, and in the lower right is a tiny icon that lets you switch to satellite view, to see public transit and traffic information, or to launch the separate Google Earth app.

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Ben then uses the rest of the article to outline five key take-home points about the current state of location marketing, and I think each one is worth a few minutes of your time.

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