I haven't actually researched this topic, but it looks like the current Lighting Camera Adapter (which is how you get a USB port) advertises "USB 3", so presuma

I haven't actually researched this topic, but it looks like the current Lighting Camera Adapter (which is how you get a USB port) advertises "USB 3", so presumably that means it offers enough power (http://www.apple.com/shop/product/MK0W2AM/A/lightning-to-usb-3-camera-adapter?fnode=91 http://www.apple.com/shop/product/MK0W2AM/A/lightning-to-usb...). (Jeremy, is that you? Long time indeed!)