4.3" eInk device w/ BlueTooth
 

So this https://shop.oaxis.com/products/inkc...nt=12133754055 is not new but when it came out it was ridiculously expensive -- for the iPhones it still is. But at $40, it's "heck, why not". While it is a case for a specific device I can't see why it wouldn't work standalone. At 1.8oz it's light enough. A few use cases come to mind immediately:

1. Boarding pass. I hate phone boarding passes -- is the battery on, is the screen on, how do you feel about handing your phone over... nah. This is better in every regard.
2. Load directions to accommodation before taking off, no worries about battery again. The description says "the InkCase to display up to 10 of your favorite pictures on the InkCase." so I will presume you can have the boarding pass, directions both and more loaded at the same time.

If you never had battery issues with your phone, good for you but I certainly had and this looks one of those things that make travelling a bit less stressful. Major downside: proprietary magnetic cable. Still, I thought it worths a try, I ordered one and will report back.

Neat idea. A friend of mine that has one (or something very similar) reports that the battery on his only lasts a day or two, and that having the bluetooth paired constantly hurts his phone's battery life, too.

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.