2500 Mah Card-Sized Power Bank

It's barely thicker than a credit card, so it disappears into my wallet flap without adding bulk. The 2500 mAh charge is just right for topping off my phone when I'm out for the evening, and the built-in Apple connector means I don't have to remember a cable.

Slid right into my jeans coin pocket and barely noticed it was there. It gave my phone just enough juice to get through a long evening out without hunting for an outlet.

I was surprised at how fast it charged my phone from empty—about 45 minutes for a full boost. The card size really does fit in my back pocket without bulging.