Being an iPhone user that uses every single function available like GPS tracking, background application support, Bluetooth, Wi-Fi, and mobile hotspot, I'm always running low on power halfway through the day.

I also carry around an iPad that is also very power-hungry also because I also turn on the mobile hotspot feature as well.

The Lifesaver by Mio pictured here is a very welcome device (that the manufacturer provided me as a sample for review), that has the capability to output at 2.1 A at 5 V making it capable of charging my iPhone really fast, as well as charging my iPad at full speed.

I've had it for over eight months now and so far so good. It hasn't failed me yet--the small size means that I only have 2600 mA hour capacity so I can't charge an iPhone and iPad, but if I need a boost to get me through the day I have it with me because its lightweight, small, and I'm more likely to carry a battery if has both those qualities.

I'm told that that it uses high quality Samsung cells inside, which puts it right at the top of some of the very best portable USB battery packs on the market.

All is not perfect with The Lifesaver however. The number one thing I have a problem with is the stylish aluminum casing. It looks beautiful, and is available in a number of colors, the edges are very sharp. If you put this battery pack next to your iPhone in the pocket, it's going to scratch things up pretty badly. I have solved this by getting a cloth case for it but its yet another thing to carry.

Overall, there's nothing else on the market that is this small that has the full 2.1 amp output on the market. If you can even find one in stock, I'd snatch it right up.