Hands-down the best e-book store available on BlackBerry 10
Kindle for BlackBerry 10 offers a massive selection of books and magazines for sale, and includes a reader which syncs up progress with multiple devices.
Even if you don't have a big budget for e-books, there are a wide range of classics available to download for free. Many books include free sample sections, too. A nice addition is the ability to have borrowed library books sent to your Kindle.
Readers can pull up definitions with the built-in dictionary or launch into Google or Wikipedia search for more in-depth research. Screen visibility can tweaked with brightness, background color, and font size. Odds are if you're a heavy reader, you're already familiar with Kindle and will be happy to see it on BlackBerry 10.