Thanks for the post this fixed my upload but the download does not work.
When I come into the page and click the link to download the image on mobile 4.2 theme I get a white page with just the word undefined.
I see it is using apex_util.get_blob_file in the url.
The images are being saved and can be open through a non mobile application.
Any help would be great. Loading and downloading is the first thing everyone does when testing my application and of course they all tell me it is broken.