Cloud-first software keeps the primary copy of your data on the vendor's servers and needs a connection to work. Local-first software reverses that: the application and its data live on your computer, and any network service is optional.
The practical benefits are offline operation, speed, and ownership. A business in an area with intermittent internet can keep trading, and the data stays under the business's control.
Aevornix is built on this model. Aevornix Payroll runs payroll on the user's own computer with statutory rules for seven countries, and Aevornix Mail encrypts mailbox credentials on the device.