LR mobile on my iPad has previously worked but will no longer sync. I have tried deleting the app and re-installing, and also 'deleting all data' on the desktop LR mobile preferences. The one thing I can not find on my Mac is the sync.lrdata file in my cache. That seemed to help previous users with this problem.
Any other suggestions?
Removing the Sync.lrdata might fix whatever the issue is. Or, at least, might trigger it to occur again. So remove the Sync.lrdata, start Lr, and then wait until it either syncs or gets stuck again and at that point create a diagnostic log which can hopefully provide some clues.
You can find the sync.lrcat here: /Users/<user>/Library/Caches/Adobe/Lightroom/Sync Data/Sync.lrdata
You can trigger the diagnostig log via LR Desktop preferences -> Lightroom Mobile and when you hold down the alt key you will notice a generate diagnostic log button
If you have still sync porblems please send the LR Desktop diagnostig log - best as a private message with a downloadable dropbox link.