Panasonic introduces a mobile power pack that can charge via USB various portable devices and phone called Pocket Power.

The Panasonic Pocket Power charges within for hours. It features automatic adjustment of the output to work with the connected devices.

You can also use the batteries inside of the Pocket Power to put them into another device, if you run out of power. The Pocket Charger comes with a charging cradle. Measurements are 39mmx85mmx20mm.
The Panasonic BQ-600K/F and BQ-600K/A will variants will go on sale on July 1st in Japan.
Via this Panasonic press-release (Japanese).