Having a portable GPS system or a navigation app loaded into a smartphone is always a good idea, especially for the directionally challenged.

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At the core of the Android app, means you will have a portable device which you can carry in your pocket and capture action as it happens.

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We also showcased the latest in portable tech as we brought you a brilliant Fire Department iPhone app that stands to save lives, and we rounded up our five favorite phone-charging green gadgets.

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The STB uses the Sling transcoder to convert your content to a compatible format, then the app wireless boots a sub-HD version to your portable device.

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Another free app due in the Apple store this month for the iPhone is GeneGroove from Portable Genomics.

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RIM's strategy is obviously riding on highly portable Adobe AIR apps and Flash support in the browser (much like Microsoft's Silverlight app strategy for Windows Phone 7), and we look forward to seeing just how well that playbook plays out in the PlayBook.

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In addition, the app's Music Play function enables quick and seamless wireless streaming of music stored on these portable devices.

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