Platform Capabilities

PWAs can use many Web Platform APIs, but support is uneven. Every capability needs feature detection, fallback UX, and target-browser testing.

Capability Families

Need	Web capability	PWA stance
Share outbound	Web Share API	Good mobile enhancement where supported
Receive shared content	Web Share Target manifest member	Useful installed-app integration, test per platform
Open files	File Handling API	Strong desktop installed-PWA feature where supported
Clipboard	Async Clipboard API	Useful but permission and gesture constrained
App badge	Badging API	Nice status indicator, not core UX
Protocol links	Protocol handlers	Good for deep links and app handoff
Local files	File System Access API or file inputs	Browser-specific; provide import/export fallback
Hardware	Web Bluetooth, USB, HID, Serial	Powerful but narrow browser support and permission-heavy
Payments	Payment Request and platform wallets	Verify country, browser, and processor support
Window chrome	Window Controls Overlay	Desktop-only enhancement, not a baseline

Feature Detection Pattern

if ('share' in navigator) {
  await navigator.share({
    title: 'Invoice',
    text: 'Invoice INV-1042',
    url: '/invoices/INV-1042',
  });
} else {
  await navigator.clipboard.writeText(location.href);
  showToast('Link copied');
}

Rule

If the capability is central to the product and only one browser supports it well, you are making a platform bet. Name that bet in the decision guide before implementation starts.