Used to be great, now freezes all the time

I used to love this app used to work great but in the past year it has become more horrible. Im not sure if the latest OS is part of the problem or what, but it has become so aggravating. It often freezes when I try to turn the page or if I hit contents and try to go back in the table of contents it will freeze between places in a book and then often it will just shut down. Closing down and restarting the app sometimes helps but then maybe a half an hour later I run into the same problem again. looking for another reading app.

Please fix it!!! I miss this app

JoeLee about Bluefire Reader