I have recently started using lightroom mobile on my iPad and it has been handy for showing people beautifully resolved copies of my work, but I was trying to upload to a photofinishing site via the iPad with no luck. The first thing I tried was sharing to iCloud but it only sends a low res version of the file. For example the image file was 5200x3200px and the file that showed up in iCloud was 2000x1300px and 996kb which is noit even close to its original size. Is it possible to get full resolution files from mobile onto my device for uploading or is this only possible with the desktop version?
Lightroom for mobile is not a backup service. Lightroom desktop does not sync your original raw files to the cloud and to Lightroom for mobile. Lightroom desktop creates and syncs images to the cloud in the form of Smart Previews. Smart Previews are smaller versions of your original files, roughly 1.5 or 2 MB in size, and retain all the flexibility of a raw file. Changes made to Smart Previews automatically sync with your originals.
Therefor Lightroom Desktop Version can do the job.
Hope it helps.