Open the app and tap the plus button in the lower corner. You can scan a book's bar code, look for it by title or writer, or type in the details yourself. Saved books show up right away on your main shelf, grouped by the categories you pick.

Yes. Tap any book cover, then choose 'Download for Offline' from the menu. Books that are downloaded have a green arrow and can be opened without an internet link. You can handle downloads in Settings to clear up space.

Go to 'Shelves' in the side panel, then tap 'New Shelf.' Give it a name (like 'Favorites' or 'To Read') and put books on it by holding down on a book cover and choosing 'Add to Shelf.' You can also add several tags to each book for better sorting.

Yes, if you make a free account. Syncing happens on its own when you are online, including your shelves, tags, and reading spot. To turn on syncing, go to Settings > Account > Turn On Cloud Sync. Changes show up on all linked devices within a few seconds.

Open Settings, then tap 'Export Data.' Choose the 'CSV' format, and the app will make a file with all titles, writers, categories, and notes. You can send it by email or save it to your cloud drive. This works on both iOS and Android.