This way should you accidentally drag one around you can see at a glance what happened and return it to its proper place. I once had this rather embarrassing episode with my ghostwriter consultant where one whole chapter got moved up to the chapter I sent off to her. Another time I somehow inserted my blank character sheet into a section and I have no idea how that happened.
Now, one of the best things I do in order to make sure there is a backup is to save my backups to the cloud too. I use different folders for each device. "Desktop" Tablet" "Laptop" That way should I find a corrupted file I immediately go back to my most recent backup and restore it. Computers were built by man so I make a point of being redundant in my backups. I also make a point of exiting out every few hours so that there is a recent compressed file on the cloud (in my case onedrive.)
However, it's odd that iOS is having dropbox issues. I wouldn't know the first thing around iOS due to being a windows girl but I believe dropbox should be a go between them, unless the windows and iOS uses a totally different save feature. Did L&L take into account that people may switch at random between versions?