BookFusion is an eBook reader and manager that allows you to easily access and organize your eBooks across all of your devices. To use the app, you will need to create an account using your email or sign in with a social media account. This account will allow you to sync your eBooks, bookmarks, comments, and highlights across all of your devices, as well as use other features such as the web reader and "send to Kindle" functionality. If you do not want to create an account, do not install the app. The app features an integrated reader that allows you to read EPUB, PDF, and CBZ/CBR eBooks both online and offline. You can customize your reading experience with various settings such as margins, line spacing, fonts, and colors. The app also offers seamless syncing, so you can pick up where you left off on any device. You can easily organize and access your eBooks using virtual bookshelves, series, categories, tags, and author filters. The app also offers a light and dark mode for your reading preference. With BookFusion, you can also highlight and annotate your eBooks with different colors and tags to keep them organized. You can export your highlights in various formats and even annotate images, tables, and graphs in PDFs. The app supports EPUB 3, which allows for rich interactivity with features like video, audio, and games. To sync your eBooks from Calibre, you will need to install the BookFusion Calibre Plugin. If you prefer to use a different reading app, BookFusion offers an "open with" feature that allows you to read your eBooks with your preferred app. The app also provides metadata and book details, as well as support for additional formats through the web app. You can also browse the store for over 70,000 free eBooks or borrow from organizations like NASA and Standard eBooks. If you have any feedback or want to chat, you can contact the BookFusion team through email or Discord. Businesses and organizations can also create their own private library to share eBooks with their members. BookFusion has a Terms of Service and Privacy Policy that can be found on their website.