I bought the iOS version and liked it enough to investigate if I should also get the Windows version. I have a project created on my iPad that I have saved in Dropbox. Opened it in the Windows version, did some heavy editing and chose the Sync to mobile device. Reported there was nothing to sync. Although I had done all that editing. Afterwards when I tried to open it on iOS, the Binder sort of flashed right to left and nothing happens. When I execute the Sync command it syncs all except one file. The last file just keeps on ticking, even over night. And the problem with opening the project remains on iOS. It opens fine on Windows. But the whole point of having two devices is to be able to work with the project in a more flexible way.
“Sync with mobile device” is only an extra precaution if both devices happened to be open simultaneously. You don’t really sync anything. You save the project in the normal way in WindowS, and close it. Wait until you see that the Dropbox app has uploaded any changes to the Dropbox server. Open the iOS app and sync, i.e. let the iDevice download any changes. When you are done on the iDevice, back out to Project view and tap the sync symbol (circular arrows). Start your Windows machine, wait for Dropbox to sync any changes, and the just open the project.
If you follow this routine everything should work.
There is not really any “sync”. Scriv on both your PC and your iDevice reads the same files. So the ‘sync’ on your iDevice is in reality a Save-command. It sves the project to the Dropbox server.