For all that the $50 Fire tablet has a 128 GB capable SDXC card slot that outclasses every other tablet in its price range, and it evolved out of Amazon's flagship e-book reader, it strangely lacks the ability to index e-books on that card. This seems like a strange oversight, given that every other media app on the tablet uses that card for downloading and storage, and its 5 GB usable internal memory isn't a lot for people who have a large library of picture-heavy e-books—especially if they want to install other apps, too.