What Is a Progressive Web App (PWA)?
A progressive web app (PWA) is a website built to behave like an installed app. It uses a web app manifest so it can be added to the home screen with its own icon and full-screen window, and a service worker so it can load fast, cache content for offline use and, on supported platforms, receive push notifications. It runs from one web codebase, updates instantly and does not need app store approval.
- A PWA is a website plus a manifest file, a service worker and HTTPS; there is no separate app binary.
- Users can install it from the browser, and it opens in its own window like an app.
- iPhone and iPad support PWAs, including web push for Home Screen web apps since iOS 16.4, but install is manual.
- PWAs avoid store review and commissions but cannot reach every native device capability.
- PWAs are often the cheapest way to give frequent users an app-like experience.
How a PWA Works
Under the hood, a PWA is a normal website built with HTML, CSS and JavaScript. Three ingredients turn it into something that feels like an app:
- HTTPS. PWAs must be served securely; browsers will not register a service worker on an insecure origin (localhost is the development exception).
- A web app manifest. A small JSON file that tells the device the app's name, icons, theme colors, start URL and display mode, so it can open full-screen or in its own window instead of a browser tab. The format is a W3C specification.
- A service worker. A script that runs in the background between the app and the network. It can cache files and data so the app loads instantly and keeps working with a poor connection, handle push messages, and sync data when the connection returns.
Because it is still the web, a PWA has a URL, can be indexed by search engines and linked from anywhere, and every user gets the latest version the next time it loads.
What PWAs Can and Cannot Do
Where they are strong
- Home-screen icon and full-screen launch on phones, and installed windows on desktop browsers such as Chrome and Edge.
- Offline or low-connectivity use for content and forms, with sync when back online.
- Push notifications on Android and desktop, and on iPhone and iPad for web apps added to the Home Screen.
- Camera access, geolocation while the app is open, payments through the browser, file uploads and most of what business apps need.
Where they fall short
- Installation on iPhone is manual. Safari does not show the automatic install prompts Chrome does on Android, so users must use the Share menu's Add to Home Screen option. Many people do not know to do this.
- Deeper device features. Background location tracking, Bluetooth accessories, NFC, health data and some sensors are limited or unavailable, especially in Safari.
- Store presence. A PWA is not automatically in the App Store or Google Play. Android PWAs can be packaged for Google Play through Trusted Web Activities, but Apple's guidelines expect apps to offer more than a repackaged website.
- Storage limits. Browsers can clear cached data under storage pressure, so a PWA should not be the only place important data lives.
Browser support changes with each release, so check current capability tables on MDN before committing to a feature you depend on.
When a PWA Is the Right Choice
A PWA fits well when users return often but the app's core job does not need hardware that only native code reaches. Good examples: customer portals, ordering and reordering, booking, internal field forms, inventory lookups, dashboards and membership content. A South Florida property manager, for example, could give tenants a PWA for maintenance requests and rent reminders without asking them to visit an app store.
It is a weaker fit for consumer apps that depend on store discovery, apps that track location in the background, apps that pair with Bluetooth hardware and games that need maximum performance. Our comparison of PWA vs native app covers these tradeoffs side by side.
Cost and Business Considerations
Because one codebase serves every platform, a PWA usually costs less to build and maintain than separate iOS and Android apps. Releases go live without store review, which removes a source of delays and rejections. Payments for digital goods are handled by your own processor, so app store commissions do not apply, though normal card processing fees do.
The cost you trade for that is discovery and install friction. Plan how users will find and install the app: links in confirmation emails and texts, a QR code at your location, and a short in-app tip on iPhone explaining Add to Home Screen.
Starting With a PWA, Moving to Native Later
A PWA is a sensible MVP format, especially when you are not yet sure whether customers will use an app-like experience at all. You learn from real usage at web speed, ship fixes the same day and avoid paying for two store submissions while the product is still changing. If usage proves out and you need features only native code reaches, the backend, APIs and much of the design carry over to a native or cross-platform app. If you are still deciding whether you need an app at all, start with app or website.
Sources and Further Reading
We link to the primary documentation so you can verify the details yourself.
- Progressive web apps, MDN Web Docs
- What are Progressive Web Apps?, web.dev (Google)
- Web Application Manifest, W3C
- Service Worker API, MDN Web Docs
- Web Push for Web Apps on iOS and iPadOS, WebKit
Related Questions
Do PWAs work on iPhone?
Yes. Safari supports installing web apps to the Home Screen, offline caching through service workers, and, since iOS and iPadOS 16.4, web push notifications for Home Screen web apps. Installation is manual through the Share menu, and some device features available to native apps are not exposed to the web.
Can a PWA be listed in the App Store or Google Play?
On Google Play, a PWA can be packaged with a Trusted Web Activity and published like an Android app. Apple's App Store expects apps to go beyond a repackaged website, so a thin wrapper around a PWA risks rejection. Microsoft's store also accepts PWAs.
Is a PWA good for SEO?
It can be, because a PWA is a website with crawlable URLs. The usual SEO rules apply: pages must render content that search engines can read, load quickly and have unique titles and descriptions. Apps that render everything client-side should be tested in Search Console.
Are PWAs secure?
They require HTTPS and run inside the browser's security sandbox, which is a solid baseline. The application itself still needs secure authentication, server-side validation and careful handling of cached data, just like any web or mobile app.