A power block ...

... First class!
Previously had a device uses Gomadic 0.7A charge current and 3000mAh capacity, which, for example, a Samsung Galaxy S3 4 times no longer wanted after. I was looking for a strong possible battery, which provides at least 1.5A Output and for repeated recharge of mobile phones guaranteed. This device I have now since Christmas always with you, if there should be a critical time.
I have to say it really invites extremely fast (as my charger to the wall socket) and can even upload additional 2 devices simultaneously!
The only drawback: in the procedure describes that you can also charge the battery while you here, other devices can connect so that they are well loaded. So far, sadly wrong :(
I charged the battery with 2A and multiple devices, which need less than 2A to load connected, but even if the button is pressed appears for a few seconds, the message will be loaded and then it's over.
So just to recharge and when he's done, you can plug in other devices. Too bad :( otherwise you might use it as a buffer if times fails electricity or on bicycle.
But that's the only thing I have to complain about. Otherwise, the capacity of 12000mAh is truly gigantic. I could theoretically 1020 6x to need my Lumia from 0 to 100% load without a power socket!
Smaller Android Tablets may thus be loaded, so almost everything to load which up to 2A needed.
Can the product really highly recommend it!