Choose local for private personal context
Ledgers, therapy exercises, faith notes, workouts, and task systems often contain context users do not expect a product company to read.
Choose private cloud for shared work
Team workflows, large documents, server-side automations, and cross-account collaboration can justify a private cloud if the security model is explicit.
Design for graceful boundaries
The strongest products make routing visible: what runs locally, what leaves the device, what is stored, and what is never retained.