A few days ago I was making a video with my iPad Air 2 camera. A pop-up alerted me that the 32GB memory was almost full, inviting me with a pop-up "Manage your space" or like this in Italian "Gestisci Spazio". I clicked the pop-up and was asked me if I would delete apps that I don't use so often. I accepted and Ipad deleted some apps. OK I said.
The day after I realized that the Books app was without my 80 books previously present! Ipad had deleted all my books whithout asking me! Very frustrating 🙁 . All my books (most of them pdf) had been downloaded from safari or emails so not from the apple store. A learned that the backup doesn't include pdf from Books, so a cannot restore an old backup I done in October 2020. I didn't have activated the iCloud Books switch in iCloud menu under settings, so not recovery is possible.
I already asked apple support without help at all. I read that I'm not alone with this big big bug.
Best Answer
Steve Jobs wanted to give his product usable and user-friendly. I think as developer and user that for iOS the combination of Itunes, Icloud and Icloud drive with all your stupid and strange sync, limitations and stupid and illogic combinations between them changing each year (Itunes doens't allow to save your book distinctly, the icloud backup some time ago saving the pdf inside ibooks app, now not anymore, but they (pdf) can be saved in icloud drive, the photo are sync in icloud but not in the backup,.. and so on..) promoted that ecosystem to be the worst and less usable implementation I could see today. Jobs said that Microsoft doesn't have taste, I think that iOS after 14 versions is also worst than MS Windows 95. I'm on the field and I'm very confused and scared to deal with an Ipad for important things, except to navigate with safari. My teams never would have designed a so painful and not usable system, complicated also for a developer. It canceled my data, but other than that I procrastinate thinking I have to find a way to save my pdf from the IPad to a PC, to save my photo etc. stupid things allowed by a 100€ phone. I have to send and email at my address to add a book to my library :-)! Read the hundreds of messages on apple community how they lost important data after the stupid connection with Itunes, that decides for itself to restore the data it decided and rewrite yours in the device. At the end of the day all that mess just to sell some extra space in icloud. Let me to pay much your device, but at least allow me to use it and manage my data. Painful!