Have you read this Topic:
No syncing to pocketpedia!
Try the following:
1 - open desktop DVDpedia and hold the Option key and click on the Help menu and this will open a hidden menu
2 - select and click on
Export for Pocketpedia
3 - save the resulting
For Pocketpedia.pocketpd file to Desktop and Quit DVDpedia
4 - connect your iDevice to your mac via cable
5 - open Finder and click on your connect iDevice in the left column under Locations
6 - let it finish completely the Sync'ing process
7 - select Files on that windows tab bar
8 - select Pocketpedia and right click on each Folder/File and select Delete. However
DO NOT DELETE the actual Pocketpedia entry
NOTE: sometime Finder does not immediately show these App's & Files, wait a few minutes.
9 - select the
For Pocketpedia.pocketpd on your Desktop and drag & drop it into Finder on top of the Files Pocketpedia entry
10 - eject your iDevice from your Mac
11 - open Pocketpedia on your iDevice and select DVDpedia within the Collections column - it should now start to reload all your entries and cover art, be patient as it may take a while. (from seconds to several minutes)
Hope this helps