"I lost all my PDF files stored in iBooks when upgrading iPad to iOS 12. Have backed up to iTunes on my computer but can't find it. Not on the iCloud as far as I know. How to recover the lost PDF on iPad?"
Lost PDFs on your iOS device? If you are looking for PDF recovery for iPad, iPhone or iPod, this content is exactly what you need. You will learn why the e-Book PDF files in iBooks are lost, and 3 workable methods to restore PDF files from iPad, iPhone and iPod touch.
All the methods apply to iPhone X/8/7/SE/6s/6s Plus/6/6 Plus/5S/5C/5/4s/4, 12.9-inch iPad Pro, 10.5-inch iPad Pro, iPad, iPad Air/mini 4/mini 3/mini 2/mini/4/3/2/1, iPod touch 5/4.
Data loss on iPhone or other devices happens frequently, and mostly the PDF files (including the non-iBooks Store book) are lost due to the following reasons:
There is a shortcut you can try to find your missing PDF files, and some users reported that it works for them.
If you have turned on Sync Collections, you can find lost PDF on another iDevice. For example, if you lost PDF in iBooks on your iPhone, you can find back the same PDF files on your iPad.
This is because the Sync Collections makes the iBooks keep your PDFs (and non-iBooks Store books) in the same collections across all your iOS devices and Mac. Like if you have the same PDF on all your devices, when you move the PDF to your Sci-Fi collection in iBooks on your iPhone, that PDF will appear in your Sci-Fi collection the next time you open iBooks on your iPad. And if you delete a copy of PDF from iPhone, it will still be on your iPhone.
Recovering data is always a very important thing you should do. We have dedicated a hot article to show you: Top 5 Options to Sync iBooks Between iPhone/iPad and Mac. You can choose to sync iBooks between different devices.
UltData is quite a helpful tool for you to recover deleted/lost data. If you have a backup file, you can recover PDF from iTunes/iCloud backup with this program. If you don't have a backup file, you are able to restore missing PDF files from device by using this software. The easy guides are as below.