Both NZ and NZM can operate on cardboxes that are synced with Dropbox cloud storage, and in that way, multiple devices can sync their cardbox/quiz-statistics databases with each other. In the case of NZ up to version 3.3.0, you won’t see any mention of syncing in the application interface, but you can use the ''Preferences'' dialog to make it look for its data directory in a location that Dropbox is passively syncing (though NZ doesn’t actually move the data for you, so you’ll have to do that yourself). If your Dropbox installation is set up for automatic syncing of the '''<tt>Dropbox</tt>''' directory in your home directory, then you should retarget NZ’s data directory to '''<tt>Dropbox/Apps/Zyzzyva</tt>''' and move your data there. Having done that, you’re now ready to sync with other desktop and mobile devices through Dropbox. NZM, on the other hand, is programmed to sync with Dropbox on its own and has buttons for that purpose. If you’re firing up a new NZM installation, and already have a usable data directory waiting in the right location on Dropbox, you can start by pressing the ''Sync'' button, signing in and giving permission when prompted, and then — please! — read the prompts about conflicted items before you agree to proceed with the sync. For first-time use, you should tell it to sync in one direction only, from Dropbox to your mobile device, by answering ''Yes'' to the first question and ''No'' to the second before answering ''Yes'' to start syncing. It will take a while, so, while and it runs, especially on iOS, you should will try to keep the app active and not put it in the background or let the your device go to sleepawake, because NZM isn’t programmed to pause a sync and finish it later; since iOS tolerates only short periods of background activity before killing an active app, and NZM isn’t programmed to pause a sync and finish you should let it later! run in the foreground. After one or more tries, having completed this initial sync, NZM will only sync files that have changed, so it’ll be very quick. The one thing to remember, to avoid disappointment, is to sync when you start cardboxing and again when you stop, because otherwise you could end up with two or more devices that both think they have newer cardbox data, and this will be flagged as a sync conflict later on.