Most battery-life extending pack tend to be brain dead, they automatically charge when they're the needed. The Wi.U is a bit different. You can set the date, time and percentage you want the charger to activate.
The iPhone isn't ideal for watching videos for a long period, it drains battery and is uncomfortable. The iKit Nu Charge's built-in battery and kickstand fix that.
The Kensington PowerBack looks like a nice little iPad battery case. And a nice little iPad kickstand. And a nice little iPad dock. That is one sexy ménage-a-Pad.
Packing a battery pack, a GPS receiver, IPX-7 waterproofability into a single case to protect the otherwise svelte iPhone sounds like overkill, but if you're going to put a case on a phone, you should do it right.