Super also play Ingress. There, the juice is known through GPS and mobile internet quickly empty. But that does not happen with your device.
To size must be said that the more juice has such a battery, of course, the units are larger.
With the size of a grade 2, it can be compared. I recommend double-sided Velcro to take. One side of the battery, the other on a mobile phone shell (if you have several). So the battery can not fall out of your hands - or the phone ... :)
Processed class did that too. The battery charge lamps are good at and like to be used as a mini flashlight, which is a small flaw, in my opinion. However, not enough to draw a star.
Super sub - Full marks.