Always Be Progressive

Progressive Web Apps are here… but what about the progressive part?

Push

What? Native support for Push Notifications and the Push API.

No support? Try using email or SMS for notifications.

Positive signals. Supports non-standard notifications on desktop only.

Available in preview. As of August 2016.

Supports spec, but on GCM endpoint. Web Push coming soon.

Full support for spec, including Web Push.

  1. Using the Push API MDN
  2. Push Codelab Google Developers

Install

What? Prompt to install. Browsers already support bookmark/install, but it's user-initiated and hidden.

No support? Use manifest helpers to create meta tags (e.g. pwacompat) and JS install widgets (e.g. Cupiq).

Limited Add To Home Screen. Enhances user-initiated install with apple-mobile-... tags.

Full support for Web App Manifest and install prompts.

  1. Increasing Engagement [...] Google Developers
  2. Firefox status Twitter

Offline

What? Support for starting offline, or working after becoming offline.

No support? Treat network as a feature, and use Web Storage API to cache content. Requires online to load, but then treat network as a feature.

Support for AppCache. Deprecated offline spec, for specific URL caching only.

Available in preview. As of August 2016.

Full support for Service Worker and its cache.

  1. Using Service Workers MDN
  2. Google search