Assuming you are using Moneydance 2017 or 2019 and as you are syncing to a mobile app then when you set up syncing all your data is synced to a folder in another folder “.moneydancesync” on Dropbox. This data is end to end symmetric AES256 encrypted with the key (encryption passphrase) only being held on your devices, not in the cloud. It’s the syncing encryption passphrase that is used, not your data set password when syncing. As far as I know data such as your account information is not synced on to mobile devices but would be synced on to other synced computers. The encryption system used is as used by banks.
I'd feel better if it weren't, but knowing what's actually going on is good
I knew about the encryption, and I'm sure it's safe, but there's always
It hadn't occurred to me that data would sync between computers. I have no
need for that, but that's very cool.