progressive checklist

[jeffbcross]

Checklist of technical features to satisfy the definition of a Progressive Web App:

• App Manifest exists (install to home screen prompt)
• Manifest has theme_color, background_color, >= 192px icons
• Registered SW with caching of app shell and static assets
• Push notifications (optional)
• App navigable without browser back button
• App shell has viewport meta tag
• App shell exists with network-unblocked critical render path
• Site served on HTTPS