I am trying to find a solution to ditch calibre(at least for library management) completely, and with the advent of cheap android eink devices, this seems more possible now. A simple app that communicates with a web backend to manage my library on such a device would be enough.

one recently released such device is Boyue T62 (http://www.banggood.com/Boyue-T62-8G-Dual-Core-6-Inch-WIFI-A...) Here is an overview (the review is for the same device, just rebranded and with previos generation specs) http://blog.the-ebook-reader.com/2014/08/11/icarus-illumina-...

You also get much better pdf reading capabilities with these devices.

Until the next generation displays for reading come into play, these look much better overall than kindle, nook, etc.