The iPad's 10+ hour battery life is one of its many appealing traits. But when even that's not enough, Kensington's $150 PowerBack adds another five hours between charges.
That's enough for non-stop use from Sydney or Melbourne through to LA or San Francisco plus a few hours in the lounge beforehand, and you'll still have enough juice to log into a wi-fi hotspot, catch up with the news and check your email when you arrive.
The PowerBack's battery is built into a professional-looking iPad case with a rear kickstand that allows a variety of portrait and landscape orientations.
A chamber on the bottom edge of the case deflects the sound from the iPad's speaker back to face you, making a noticeable difference in volume for those times you're not using headphones.
Once your iPad is snug in the tight-fitting case, the PowerBack supplements the tablet's own battery (with an LED 'fuel gauge' to show the amount of charge left) until both tanks are dry.
One downside is that the case fits over the iPad's dock connector – so you won't be able to use a video out adapter or Apple's Camera Connection Kit.
Given that it can be tricky to get your iPad in or out of the case, that's an oversight we wish Kensington had worked around. You can still sync and charge the iPad via the supplied micro-USB cable, however.
We'd also suggest you look at a generous-fitting slip case for the iPad, as this case still leaves the screen unprotected against scuffs and scratches when not in use.