Had a book as a pdf file stored on Document Cloud, and read it through Adobe Acrobat on my Ipad. Most of the reading took place when I didn't have internet access, and I guess the document was stored as some kind of cache file on the device. Every time I started, I was on the same place with all comments and underlining still there. But then, at one point, I was asked to log in to the Document Cloud again. Now the document was clean, as if it had synced to the cloud stored version before I went off line, and not to the local stored one.
Is there any chance that I could recover my comments and underlining (there was a lot of them!) on my Ipad?
I am sorry that you were signed out unexpectedly and lost comments. Unfortunately, there is no recovery feature for the files stored in the Document Cloud.
Would you please check various file locations (Recent, Local, Document Cloud) to see if you can find multiple copies of the PDF document?
In general, it is highly recommended that you close and re-open a PDF document frequently to force saving changes before your iPad/iPhone goes to sleep or offline.
Sorry for the inconvenience this may have caused.
We just released Acrobat Reader for iOS version 16.04.05 on March 30, 2016.
This release includes the fix for the "sign out" problem that you may have experienced.
Would you please update to the latest version and see if it works for you?