I left this out of my review of the Gionee M2, but it is one of the truly remarkable features of that phone: the M2 doubles as a power bank. You can charge your other phone or run a small USB fan by plugging them in to your M2. Remember that the M3 has a huge 4200mAh battery? With a battery capacity that huge, why not? You get the picture now. Have a look at the M2 in action powering a fan:
And here it is charging a BlackBerry smartphone:
Is the Gionee M2 cool or what?