Here is a carabiner with a 3000mAh power bank inside that can recharge your smartphone 2 times. The Re-Fuel Powerbiner adds over 11 hours of video time, so you can do more on your iPhone while spending time outdoors. The carabiner clip can hold up to 132lbs. It comes with overcharge and short-circuit protection and works with all USB powered devices.
This carabiner power bank has an anodized aluminum clip. It is available for under $40 at this time.[where to get it]