Answer

Can a PWA register a custom URL protocol?

Short answer

Yes. An installed PWA can register itself as the handler for a custom URL scheme (prefixed with "web+", e.g. web+myapp://) using the manifest’s protocol_handlers field, so clicking such a link anywhere on the OS opens the PWA with that URL — the same mechanism native apps use for schemes like mailto: or spotify:. It is supported on Chromium browsers; not on iOS Safari.

By InstantPWA engineering·Reviewed July 25, 2026

Manifest configuration

protocol_handlers declares the protocol name and a url template containing "%s", which is substituted with the encoded target URL when a matching link is clicked.

Naming rule

Custom protocols must be prefixed with "web+" unless registering one of a small allow-listed set like mailto: or tel:.

Support

Chromium desktop and Android for installed PWAs only; not implemented in Safari or Firefox.

Sources

web.dev — URL Protocol Handler registration

Related

Can a PWA be the default handler for a file type?

Yes, on desktop Chromium browsers. The File Handling API lets an installed PWA declare file_handlers in its manifest, associating file extensions or MIME types with the app so double-clicking a matching file (or right-clicking → Open With) launches the PWA with that file passed in via the launchQueue. This is not supported on iOS or Firefox.

What is a Web App Manifest?

A Web App Manifest is a JSON file — usually manifest.webmanifest — that declares your app’s name, icons, start URL, theme colour and display mode. Browsers read it to decide whether to offer the install prompt and what icon and name to show on the home screen.

How many users actually install PWAs?

There is no single industry-wide install rate — it depends heavily on the product, audience and how the install prompt is presented. What is well documented is that several large companies (Twitter/X with Twitter Lite, Starbucks, Pinterest, Uber) have published PWA case studies reporting improved engagement, load times or conversion after launch, which is why PWAs remain a common choice for content and commerce sites.

What are some well-known examples of PWAs?

Well-documented production PWAs include Twitter Lite (X’s lightweight PWA for low-bandwidth markets), the Starbucks ordering PWA (built for reliable performance on slow connections), Pinterest’s mobile web PWA, and Uber’s m.uber.com PWA designed to work on low-end feature phones. Each company has published its own case study describing the goals and outcomes of its build.

PWA vs AMP: what is the difference?

AMP (Accelerated Mobile Pages) is a restricted HTML/JS framework designed to guarantee fast-loading static content, historically used to qualify for special placement in Google’s mobile search results. A PWA is a broader architectural pattern — HTTPS, manifest, service worker — that adds installability and offline support to any site, including AMP pages. They solve different problems and are not mutually exclusive, though AMP’s search-placement benefits have diminished since Google ended the AMP requirement for the Top Stories carousel in 2021.