Im a sucker for sunk costs. I have had a nook for about 5 years now and have spent my fair share on ebooks. I wish there were more sharing among e-readers but I suppose that would go against normal business sense. Itd be great for us consumers though! At any rate, Im a nook until B&N goes out of business.
The app is getting better. I use an iOS device when i am not using my nook e-reader. There were a couple years there when my devices wouldnt sync up. Quite frustrating. This seems to have remedied itself in recent months.
allfam about Barnes & Noble NOOK, v4.5.1