It's really too soon to rate this app. Since it's free - at the moment - you can download and try it without risk. It's certainly easier to use for reading ePubs than calibre, which is primarily an ePub creation tool. Needless to say, it's a work in progress, but it did OK with two ePubs I tried it with. It's a little slow yet. Hopefully performance will improve. And the choice of fonts is quite limited, though Helvetica and Georgia are adequate, I suppose. The one thing that might annoy some users is the book-like interface, but that's an option that can be turned off. I'm looking forward to future developments. As an e-reader Bookinist is a off to a good start - though the name leaves something to be desired. One suggestion to those trying it out: If you click the full-screen button in the upper right-hand corner, Bookinist moves into its own desktop space, which is OK if you're accustomed to that behavior. If you prefer not to deal with spaces, just click the green window button - you'll get the same full screen effect without changing desktops.