Limited battery life and the proprietary cable are discouraging notes. It doesn't work with the Kindle, which is kind of a bummer but it makes sense; Amazon wants you to buy their reader.

I do like the idea of having stored persistent images for maps, coupons, reservations, and boarding passes. I hate being "that guy" who needs to spend time messing with the phone at the front of the line. I wonder if it would work with the Starbucks app? I'm not sure if the barcode presented by the app changes or not.