The Pros of the Dynamo on the Go are it’s high capacity at 10400 mAh, as well as having dual outputs, One at 2.1 Amp, and one at 1 Amp, both of which can be used simultaneously with the current not being diminished. Price, it’s only $29.99 USD. the unit is lightweight, and thus highly portable, you can even take it in your pocket.
Takes about 11 hours to fully charge as it has an internal charging limit circuit that maxes at 1 Amp. The charger it comes with is sufficient due to it’s internal charging limit. The two short micro USB cords it comes with feel a bit cheap, though they do the trick. It also does not feature pass through charging, so no charging your devices while this baby charges. Piano black shows fingerprints and everything else.
The Dynamo on the Go is one of the best battery packs I’ve used with 2 USB ports that deliver 2.1 and 1 Amps of current to your devices, it charges via micro USB, has a great power indicator to let you know roughly how much juice is left. I was able to recharge a Nexus 4, 2 Galaxy S III’s and a feature phone while camping on a single charge.
All in all this battery pack is a must have item for anyone with a smartphone or tablet, including i-Devices, and anything else that you can charge via a USB port.
RAVPower® 10400mAh External Battery Pack
Some pictures of the unit as well as some comparison shots to my Anker Astro 3 E 10K