The term "progressive web app" was coined by Google engineers in 2015 and has steadily grown in importance since. Major companies — including Starbucks, Pinterest, Twitter, and the BBC — use PWAs to deliver fast, reliable experiences to mobile users without the friction of an app store download. The technology is now mature and well-supported across all modern browsers and devices.
What Makes a Website a Progressive Web App?
Three technical features turn a standard website into a PWA:
- A web app manifest. This is a small file that tells the browser how to display your website when it is installed on a phone — what icon to show on the home screen, what name to display, whether to show the browser address bar, and what colours to use. Without a manifest, a website cannot be installed as a PWA.
- A service worker. This is background code that sits between your website and the internet, caching pages and resources so that the site loads instantly — even on slow connections — and displays a useful page rather than an error when the visitor has no internet access at all. Service workers are what make PWAs work offline.
- HTTPS. PWAs must be served over a secure connection. Fortunately, any modern website should already have this — the padlock icon in the browser address bar confirms it. If your site does not have HTTPS, that is a more fundamental issue to fix first.
What Can a PWA Do That a Regular Website Cannot?
The most useful PWA capabilities for small businesses are:
- Home screen installation. When a visitor opens your PWA in their browser, they can be prompted to add it to their phone's home screen. From then on, they open it by tapping your icon — just like any other app — rather than typing your web address. This makes it much more likely that customers will return repeatedly.
- Offline access. The service worker caches key pages and content. If a customer is on the Underground, in a rural area, or anywhere with no signal, they can still open your PWA and see your menu, your contact details, or your portfolio. A standard website would show a "No internet connection" error in the same situation.
- Push notifications. With a PWA, you can send notifications to customers' phones — even when they are not actively using your site. This can be used for appointment reminders, new product announcements, or special offers. On Android, this works reliably. On iPhone, Apple added PWA push notification support from iOS 16.4 onwards, though it requires the customer to have added your PWA to their home screen first.
- Faster loading. Because a service worker pre-caches resources, a well-built PWA often loads in under a second on repeat visits — significantly faster than a cold page load from a standard website.
Who Actually Benefits From a PWA?
PWAs are most valuable for businesses where customers interact with the website repeatedly and regularly. Think about a café whose regulars check the weekly specials menu, a yoga studio whose clients book classes through the website, or a takeaway restaurant where customers order online every week. In these cases, having an icon on the customer's home screen and being able to send the occasional push notification has genuine commercial value.
For a plumber, a solicitor, a decorator, or any service business where most customers visit the website once — to find your number and make contact — a PWA adds complexity without meaningful benefit. What matters for those businesses is a fast, professional, well-optimised standard website that makes it easy to get in touch.
How Much Does a PWA Cost?
Converting an existing website into a PWA typically adds to the development cost, since a developer needs to write and configure the service worker and manifest file. For a simple brochure site, this might add a few hundred pounds to the project cost. For a more complex site with offline content requirements, the cost will be higher.
Website builders like Wix and Squarespace have limited PWA support — their platforms handle some PWA features automatically, but not the full capability set. If you want a fully featured PWA, a custom-built site gives you more control over the result.
Do You Need a PWA or Just a Fast Website?
The honest answer for most small businesses is: you do not need a PWA yet. What you need is a website that loads quickly, looks professional on mobile, is easy to navigate, and makes it straightforward for visitors to contact you. Get those fundamentals right first.
If your business reaches the point where customers are regularly using your website as part of their daily routine — checking menus, booking appointments, placing repeat orders — then a PWA becomes a genuinely worthwhile investment. At that stage, the home screen presence and push notification capability start to deliver real competitive advantage over a standard website.