Features include the ability to search and browse by artist, album or track, create playlists and download music from Cloud Player to the device for offline playback.

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The company posted an explanation this week, predictably pointing the finger at Amazon Web Services and explaining that not every streaming device was knocked offline.

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Anyone with a good customer relationship or contact management system will likely want to bring their contacts and calendar down to their device to look at offline.

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Combine these offline capabilities with device APIs that allow web apps to access hardware features like cameras, battery level, microphone, etc and Mozilla could effectively break down the barriers not only between HTML5 and native apps, but between high-end mobile devices and low.

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It can even generate an offline playlist on the device -- something similar in spirit to a feature I've long wanted on the iPod and other players, which is to be able to "switch gears" while listening in shuffle mode to play more tracks from just that artist, the rest of the album, or other songs like the one I've heard.

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The company has been testing offline modes through its PayPal Here device and announced a tie-up with Discover Financial Services in Q3.

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And, unlike traditional cash registers, a mobile device can easily be slipped under a coat and carried out of the store for offline analysis.

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All files stored on Transporter are available from any computer or mobile device that has access to the Internet, and files can also be synced for offline access.

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