Having extra battery power is the most important aspect of conference preparedness.
The E71 even manages to squeeze in extra battery, with 20 days of standby, 10.5 hours of GSM talk or 4.5 hours of 3G talk.
You also have to keep Bluetooth running on your smartphone, with the extra battery drain on the handset, which may be of concern to some users.
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According to a LeapFrog rep, this allows for an extra hour of battery life from that of the previous generation.
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Kindle Paperwhite is the most-advanced e-reader ever constructed with 62% more pixels and 25% increased contrast, a patented built-in front light for reading in all lighting conditions, extra-long battery life, and a thin and light design.
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Wysips says its 0.5 millimeter-thick screen can be plugged directly to the phone's power inlet to provide an extra four minutes of battery life for every 10 minutes it is exposed to direct sunlight.
Then a third friend gets excited and adds some extra speeds and a better battery.
The battery compartment also needs extra packaging, and it adds to the complexity and the size of the device.
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For users dead set on expanding that capacity, an optional keyboard dock will be made available that not only augments the S2110's storage via full SD slot, but also extends battery life by an extra 10 hours.
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Apple took advantage of the extra room to beef up the battery and the company claims 8 hours of browsing via a cellular connection, 8 hours of talk time or up to 10 hours of video playback.
V-MODA's analog noise isolation naturally blocks out the distractions of jet engines, outside noise and booth monitors minus the extra digital-to-analog conversions of battery powered headphones that pollute the purity of your music.
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The immediate goal is to develop a secondary battery for an EV that could provide extra mileage in a matter of seconds.
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Obviously, the question remains how big of a trade-off there is on battery life in exchange for those two extra cores and the more powerful graphics chip.
Again, you're looking at a heavier machine -- 6.05 pounds in this case -- but the extra screen real estate and larger six-cell battery may make it worth it for some.
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It might be missing the PureView camera, but it has a perfectly reasonable Carl Zeiss lensed standard camera, removable battery, support for MicroSD cards for extra storage, and runs everything the Lumia 920 does.
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My ancient cell phone's gas gauge is similarly overoptimistic, and as its aging battery holds less charge than ever, the extra-big spare keeps me connected.
It may not get down to the nearly anorexic 7.1mm of the Droid RAZR, but that extra volume is put to good use by the 2, 500mAh battery which, as we'll see later, stomps all over its predecessor.
Better still, battery life didn't seem to take a hit even with the extra performance, though high-end, high-res gaming was still a lesson in futility when working without a discrete graphics card.
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With the environmental benefits of a hybrid come environmental costs: 30 extra pounds of copper, mostly in the motor windings, and 22 pounds of nickel in the battery.
There's 4GB of memory and a 128GB SDD in all three, while the hybrid bucks the trend by offering a removable battery, with both the faster Core i5 and the Core i7 models coming with an extra cell bundled in.
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