If you have MoneyWiz Premium subscription, background sync is automatically enabled for you (you don't need to enable anything). Background sync will attempt to periodically perform the following tasks:
perform a MoneyWiz Cloud sync cycle (download changes to your data from other devices and upload your local changes to MoneyWiz Cloud),
perform an Online Banking refresh (download data from your banks),
perform a Spotlight indexing cycle.
We've implemented this feature according to official Apple's guidelines. Sadly, this means that the following limitations are in place:
It's the operating system's decision as to when to perform background refresh, not us. This means that it's entirely possible for MoneyWiz not to do any background refresh in the first 22 hours of the day and then in the last 2 hours perform 3 refreshes.
When your operating system initiates a background refresh, it gives MoneyWiz just 25 seconds to complete the task. When the time is up -- that's it and the process is halted.
We hope that in future releases of its operating systems, Apple will improve the background refresh feature. Any improvements they make would automatically translate to improvements in background sync for MoneyWiz as we're using Apple's native implementation.
In the meantime we also look for some custom implementations of the same to work around limitations of Apple's current implementation.