I got this at the till while buying socks in San Mateo for 5 dollars.
- What is it?
A small prism with a male foldable USB socket on one end, a female USB socket, a battery in the middle, a tiny button and tiny led.
- How does it work?
When you are plugging stuff to charge via USB, you plug this in the middle, so computer -> backup battery -> gadget. That charges the gadget and the backup battery. Then you throw it in your pocket/bag when you leave home.
- What does it do?
It lets you recharge roughly half a phone's full charge, when you inevitably run out of battery, so unless you forget to charge both things, you'll manage to survive.
- What could be better?
It could come with a micro-usb male instead of a USB female, because that means you also have to carry a cable (no big deal)
- What does the button do?
It stops/starts the current flow into the gadget.
- What does the LED do?
Tells you if current is flowing (green) or if it's charging (red).
- Can you charge anything?
Yes, but 750mAh is enough to keep a Nexus 7 working for about 30 seconds ;-) Does a decent job on a Kindle though!
- Are you going to lose it?
Oh yes, the thing is tiny.
Not a bad 5 dollar gadget. However, you can find it in Amazon for $30 at some places, and that's robbery.