The Nook HD+ was a nice media consumption tablet for its time but it was crippled at launch by a lack of content. Tying it to the...sparse... Nook media store was not helpful. By the time B&N gave up fighting users over sideloading and tied it to the Play store they had already started spiraling to disaster and Play store access only served to facilitate the exodus away from the Nook store.
https://en.m.wikipedia.org/wiki/Nook_HD