You can get quite a few different kinds of cases for your iPhone. There are cases with wallets, tools and batteries made with different kinds of metals, plastics and leathers, but few of them off the utility or cool factor you’ll get with this new e-ink case from popSLATE. The small and lightweight case is available in black or white, for iPhone 5/5S/6 and gives you the same amount of protection you’re used to for a standard snap in case. The similarities with other cases end there because the back of this case has a built-in 4″ e-ink display that you can use for boarding passes, concerts photos, maps, calendars, to-do lists and anything else you might want to see for an extended period of time that looks good in black and white. Use the popSLATE app to choose whatever image you’d like to display. Send it to the case with bluetooth. Repeat as necessary.