Mehwish K.
That is correct, I have my aviation publication in PDF on my android tablet (Galaxy Tab S 8.4). The file is located in a folder and if I rename that folder or file the bookmark disappears, but as soon as I put the file or folder back to the original name/names from when the bookmark was created, they reappear. Also these PDFs are backed up in the acrobat.com cloud, if I open the file on my phone (Note 4) the bookmarks are there too.
I do have to say that by renaming the file it putting the bookmarks back is a nice feature, b/c my publications expire anywhere from monthly to annually, and when the new publication comes out i put it in the folder where the expired publication is and rename the new file to what the old file is and all the bookmarks appear in the new file since its in the same location with the same name as the file that had the bookmarks.