Oxford Street 12000Mah usb battery pack used for playing Ingress with a SGS3. Gave 4 hours constant Ingress scanner usage, followed by 5 hours using SGS3 WiFi tethered to my netbook. Usually a full charged SGS3 lasts a couple of hours while playing Ingress. Now I can go out all day and the phone stays at about 90% throughout with the Ingress app on all day.
The casing is very well built, with good rounded edges, if a little slippy. I have it in a zipped pocket inside my jacket so it won't drop out if I lean down to tie my shoelaces. It is less heavy and bulky than I expected, I do not notice it in my pocket.
I was disappointed to find it will not charge my nicolites e cigs. They begin charging but the Oxford Street battery does not recognize there's something plugged in an swithces off. But as there are two usb outlets, I can charge my ecig batteries as long as I am charging my SGS3 at the same time, because that keeps the battery pack activated.
It will also not recognize my old Nokia phone, switches off after the normal ten second shut down period. But I do not use the old Nokia anymore.
Oxford Street 12000Mah takes about 6 hours to charge back up from empty, through my netbook usb.
Really very useful battery pack and I'm surprised by the good quality casing considering this is the cheapest of the type I found after looking at a dozen.