PWA & Offline Shopping: Maximizing Mobile Conversion with Resilient Architecture

Over 75% of global e-commerce traffic originates from mobile handsets. However, conversion rates on mobile persistently lag at nearly half of desktop benchmarks.

The root causes are twofold:

• App Store Install Friction: Demanding that an ad or search visitor download a 100MB+ native binary results in an immediate 85%+ funnel drop-off.
• Network Volatility: Commuters encountering elevator rides, subway tunnels, or weak cell towers face blank loading states and dropped checkout requests.

The diagram above illustrates how Stilmerce handles cart mutations during connection dropouts without losing user intent or causing duplicate stock deductions.

Crucially, every queued transaction generates a unique client-side Idempotency-Key (UUID v4). When connectivity resumes, the background synchronization worker replays pending requests. The NestJS backend enforces atomic idempotency via Redis before decrementing physical stock.

Blindly caching everything causes stale inventory states and storage bloat. Stilmerce implements a strictly differentiated three-tier caching hierarchy:

• Static Assets: Cache-First with immutable content hashes.
• Product Imagery: Stale-While-Revalidate with strict LRU eviction (cap of 60 images, 14-day TTL).
• Stock & Price Endpoints: Network-First with a 2-second timeout guard, falling back to cached snapshots with an explicit offline UI banner.

A complete manifest.webmanifest transforms a web tab into an OS-level experience with standalone windowing and native touch shortcuts.

Detailed comparison between Native App development, legacy responsive mobile web, and Stilmerce PWA across operational, commercial, and technical dimensions.

WebKit's aggressive storage eviction policies (7-day idle deletion) and iOS 16.4+ Web Push prerequisites require explicit handling. Stilmerce requests navigator.storage.persist() and guides users through seamless standalone installation.