Secure mobile notes with explicit data boundaries — Mobile Case Study
MOBILE · secure mobile app · on-device data · privacy by design · auditable systems · native mobile
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Problem context
The system required a simple mobile experience for sensitive user data where behavior remains understandable and controllable over time.
Constraints
- Clear separation between local data and any export or sync paths
- No implicit background behavior
- Minimal surface area for data leakage
Engineering decisions
Decision: On-device first data model
Reason: Keeps data ownership explicit and reduces systemic risk.
Trade-off: —
Decision: Explicit user-triggered actions only
Reason: Eliminates hidden state changes and improves auditability.
Trade-off: —
System overview
Native mobile app with on-device storage; explicit export/sync paths. No client logos.
Outcome
Predictable data behavior. Lower maintenance and security risk.
Engagement delivered under NDA. Details anonymized.