Like a lot of these battery packs, the PocketCell has a set of four LED lights that indicates how much juice it's got left. Another nice feature: the PocketCell will automatically turn to sleep mode to save energy if you stop using it for 10 seconds (in other words, if you accidentally leave it on after you unplug it from your device, it will go to sleep by itself).
In all, the Innergie PocketCell Rechargeable Battery Bank is an impressive little portable charging option. My only gripe is that it's fairly pricey. It lists for $79.99 but can be had for around $60 online. There are certainly cheaper external battery options out there -- for instance, Monoprice sells a 3,000mAh battery charger for around $20 -- though few that include a universal charging cable (the Magic Cable 3-in-1 sells separately for $19.99 in case you lose it). This model is also smaller than many of the compact, brick-style chargers.
Bottom line: The combination of the 3-in-1 cable and the battery pack's appealing design makes the Innergie PocketCell one of the better portable chargers out there. It's just not a bargain.