PalmOilRipenessDetection-Python/frontend/MOBILE_OPTIMIZATION.md

Phase 3: Mobile Web Optimization & Local Persistence

Responsive UI Stacking

The interface has been upgraded to a Mobile-First Responsive Layout. Using CSS Media Queries, the "Scanner" and "Vault" views now transition from a dual-column desktop view to a single-column stacked view on devices with widths less than 768px.

• Touch Targets: The "Upload Zone" has been optimized with increased padding and a larger click area to accommodate mobile touch gestures.
• Dynamic Scaling: The detection overlay logic utilizes a relative scaling factor ($Scale = \frac{ContainerWidth}{ImageWidth}$) which recalculates on every scan to ensure bounding boxes perfectly align with the responsive canvas on any screen size.

Local Persistence (The Vault)

The system now features a robust Local Persistence Layer via the LocalHistoryService. This replaces the previous FastAPI backend dependency for history tracking.

• LocalStorage Integration: All scan results, including MPOB summary counts, latency metrics, and detection box coordinates, are serialized and stored in the browser's localStorage.
• Asset Archiving: To support offline review, the system captures a Base64 string of the processed image, allowing users to review detection boxes in the "Vault" even after the original file is no longer available.
• Overflow Protection: The local vault is capped at the 20 most recent records to prevent browser memory overflow while maintaining a functional audit trail for field harvesters.

Mobile Integration Checklist

Task	Status	Implementation Detail
Viewport Scaling	Configured	Meta tag set to width=device-width.
Column Stacking	Active	Media queries applied to Analyzer and History rows.
Canvas Auto-Resize	Active	Logic tied to parentElement.clientWidth.
Persistent Vault	Active	Powered by LocalHistoryService and localStorage.