I seem to be completely stuck. Proofreading a PhD thesis and made numerous annotations in the Acrobat IPad app. Emailed the pdf to the student and things seemed fine until today. The file still shows annotations from yesterday but today's are completely gone. The student mailed me first about blank pages and later about a corrupt file error. I just opened both the file from the sent folder (within the Adobe app) and the file I had in the app and they lack today's work.
This is a known defect in Acrobat Reader for iOS 15.2.x. We have already fixed the defect and submitted the new version containing the fix to the App Store for review. Upon Apple's approval, the new version of the app will become available in the App Store.
In the interim, would you please try one of the following workarounds?
(a) Use the desktop version of Acrobat Reader on a Windows/Mac computer (instead of using Acrobat Reader for iOS on your iPad).
(b) Close the PDF document with newly added annotations often to force-save changes in Acrobat Reader for iOS.
We apologize for the inconvenience this may have caused.
We just released Acrobat Reader for iOS version 15.3.0 on January 5, 2016.
This release includes the fix for the defect that you may have encountered.
Would you please give it a try and let us know if it works for you?