I sell sports card through eBay and occasionally setup listings with Variations. For simplicity I take all my photos for the sports cards on my phone through the eBay app. The problem I have is I don't believe the app offers the ability to take photos and directly assign them to each of the variations I'm listing.
If this feature doesn't exist currently, it would be nice to see in the future. Or at the very least, allow the ability to take all my variation photos, then reassign them through the desktop version of eBay. At the moment, all I see is the ability to either upload exisitng photos or reference one through URL.