TrustedReviews have looked at the Exspect ReCharge4 Portable Power Supply

The problem with handheld devices is that they have an annoying habit of running out of juice at the most inopportune moments. There’s nothing worse than being stuck on a train or a plane with a dead MP3 player or handheld console, and if you’re embarking on a long haul flight that scenario is often unavoidable. If only there was some way of recharging your device, while continuing to use it – well actually there is.

Exspect ReCharge4 Portable Power Supply Review