Did you find a solution? I've not tried LR mobile on an iOS device yet, but I am having all sorts of issues trying to use the app on my Samsung Galaxy Note 10.1 (2014 edition), that also has additional storage.
When I was working online the whole process was very, painstakingly slow. Thinking it would be faster to work offline with the images downloaded, I decided to try working offline. It took two days to initally sync and download 1,200 photos. Now not all of the images will load properly, often showing me a blank or white screen instead. If I try multiple times, occasionally the image will load. If the image does load the only thing I seem to be able to edit is the white balance. No other changes seem to register.
I purchased this package with plans to edit my photos during my commute to work. Instead all I can do is look at some of them occassionally. It is very disappointing.
Please check is there any pending updates for Lightroom mobile app on the Andriod device? It should be V 2.3.3
I'm running V 2.3.3 on my device.
I spent considerable time over a few weeks with Adobe Support, the logged into my computer and tried all sorts of things but in the end I had to remove all my collections, uninstall the app and resync (again paiiiinfully slow). I'm using v2.3.3 and LR desktop has been updated twice throughout this with no change.
I've stopped using LR Mobile on Android as even after i wiped it i'd say the sync is about 4 times slower than on an iOS device (don't get me wrong its still ridiculously slow on iOS (I have a 100Mbps connection). Opening a collection is always a collection of grey squares that load after a few minutes and it's hit and miss if offline actually works.
On iOS the sync in faster, the grey squares only appear for a short time and i've been happily triaging images this way with no sync issues.
When my subscription is due i will definitely reconsider renewal if things haven't improved as we are paying Adobe good money and the experience does not work well currently. Also annoyed they announced a price increase on a product that has not been fully developed.