What is a PWA (Progressive Web App)
Also known as: Progressive Web App, installable web app
A PWA, short for Progressive Web App, is an app built with web technologies that offers an experience similar to a native app. Like a website, it runs on many devices from a single codebase. Like an app, it can be installed, open in its own window, work offline and integrate with the system, without necessarily going through an app store.
A gym chain wanted an app for members to check the day's workout. Two native apps, one for Android and one for iPhone, would mean two projects and two store submissions for every update.
The chain built a PWA: members open the address on their phone, tap install, and the icon appears on the home screen. The week's workouts are stored on the device and open even with a weak signal inside the gym. Each update ships like a website update.
What a PWA needs to be installable
According to MDN's documentation, the minimum requirements for a browser to offer installation are:
- Web app manifest: a JSON file, linked from every page, with name, icons and display mode. Chromium based browsers, such as Chrome and Edge, require 192 and 512 pixel icons, a start URL and a display mode.
- HTTPS: the PWA must be served over a secure connection, or from localhost during development.
- Service worker: not required for installation, but it is the piece that enables offline use, storing files on the device and background work.
The three pillars
web.dev, the Chrome team's portal, sums up a good PWA in three words: capable, reliable and installable. Capable, because it uses features that used to be native only, such as notifications and file access. Reliable, because it responds quickly and stays useful on a flaky network. Installable, because it leaves the browser tab and gets its own window, icon and shortcut.
PWA, website and native app
| Regular site | PWA | Native app | |
|---|---|---|---|
| Installation | Not installable | Through the browser or a store | Through a store |
| Codebase | One | One | One per platform |
| Offline | Does not work | Works, if built for it | Works |
| Updates | Instant | Instant | Depends on the store and the user |
| Shows up on Google | Yes | Yes | Through its store page |
PWAs and SEO
A PWA is still a website: its pages can be crawled, indexed and shown in Search like any other. Google applies the same standard to all pages regardless of the technology used to build them, so being a PWA gives no ranking advantage by itself.
The caution is technical: if content depends on JavaScript to appear, each page still needs its own URL and content Google's crawler can read.
When it is worth it
- When users come back often and benefit from a home screen icon.
- When maintaining two native apps costs more than the project justifies.
- When users have unstable connections and content must load anyway.
- When the company wants to ship updates without waiting for store approval.
- If the product depends on device features the web still cannot reach for your audience, a native app remains the way to go.
PWAs in app stores
A PWA that meets the installability requirements can also be packaged and published in stores. MDN points to guides for Google Play, the Microsoft Store and the Meta Quest Store, and the PWABuilder tool simplifies the packaging.
Frequently asked questions
What is a PWA?
An app built with web technologies that can be installed, open in its own window and work offline, with a single codebase for many devices.
Does a PWA need to be in an app store?
No. It can be installed straight from the browser. If the company wants, a PWA can also be published in stores such as Google Play and the Microsoft Store.
Do PWAs work offline?
They can, if built for it with a service worker, which stores files and data on the device.
Does a PWA improve SEO?
Not by itself. For Google, a PWA is a website like any other. It needs crawlable pages with readable content and a good experience.
What is the difference between a PWA and AMP?
AMP is a lightweight page format built to load fast. A PWA is a set of features that turns a website into an installable app. Neither depends on the other.
Related terms
- AMPAMP is an open source framework for building light, fast pages, launched by Google in 2015 as Accelerated...
- Core Web VitalsCore Web Vitals are three metrics that measure the real experience of people visiting a page: LCP, how long...
- IndexingIndexing is the stage where Google analyzes the content of a page it has already crawled, works out what it...
- Landing pageA landing page is the page a person reaches after clicking an ad, email or link, built to lead to a single...
- Conversion rateConversion rate is the percentage of people who took the desired action out of everyone who had the chance...
- Customer journeyThe customer journey is the path a person takes from the first sign of a need to the purchase, and beyond it...
Rodrigo Fávaro
Founder of ROO3, a marketing and technology agency in São José do Rio Preto, Brazil. Builds AI products running in production (Tobia, gerar.app, Pense Mercado) and maintains the AI Benchmark, a public ranking of AI models.
X @rodmf LinkedIn rodrigofavaroMarketing you can measure, from the ad to the sale.
ROO3 builds and runs paid media, SEO and websites with real targets, dashboards and numbers. The first conversation is free.