What is a Progressive Web Application?

Progressive Web Apps are the future of mobile developmentWe’ve come a long way since the early days of the Web. Back in the 90’s, web pages were mostly text and images, especially large ones, were interlaced GIFs. All of this was done to save time and bandwidth and allow pages to load faster.

But greater bandwidth became more accessible and the browsers and servers became more efficient at serving pages. Developers optimized their code, streaming made it possible to watch video without having to download an entire video first, and caching made even the most graphics intensive pages load quickly.

Then we experienced the Web’s second evolution – mobile browsing. Mobile has rapidly moved from an occasional convenience to the main method of Web access for some. In fact, at the end of 2017, there were 4.1 billion internet users worldwide, with 52.9% of that population accessing the internet from their mobile phone. By 2019 that is expected to grow to 63.4%. With more than half of today’s Web searches being done on a mobile device, it’s clear that a mobile-first approach to web development is the only way to go.

But mobile browsing still experiences some of the same challenges that we had in the early days of the web. Slow page loading and spotty network access can lead to frustrated visitors. Google found that around 53% of consumers will abandon a website that doesn’t load in 3 seconds. But you have no control over a mobile user’s network access or performance.

Just as the first evolution of the Web led to more efficient page delivery, so will the next evolution, and it’s already begun. In 2016, Google and Twitter spearheaded the Accelerated Mobile Pages Project, and from that grew the idea of Progressive Web Applications (PWAs). PWAs are so important that Gartner research director Jason Wong said it wasn’t about if are going to use them, but when.

What a PWA Is

A Progressive Web Application is part mobile application, part mobile web experience, and all user focused.

A PWA has an icon on your homescreen that makes it look like any other mobile application. The functionality is very app-like, and regardless of network connectivity or speed, loads quickly for a seamless experience.

However, unlike a mobile application, a PWA has a very small memory footprint. They aren’t downloaded from an app store, and they don’t require multiple versions to support all available mobile platforms. Instead, a single implementation of a PWA works on all platforms that support the technology (at the time of this writing, Apple does not support it).

What a PWA Isn’t

A PWA isn’t a mobile application, and it’s also not a web page although it’s derived from one.

Because it’s not a mobile application, as we mentioned above, it’s not downloaded from an app store like Google Play. This means there is no delay while awaiting validation and approval. Instead, a PWA can be made available to your audience as soon as you are ready for release.

However, decoupling PWAs from mobile applications doesn’t make it just what we used to call an app-wrapped web page. Instead, it uses a combination of mobile and web technologies to provide an optimal user experience on a mobile device.

The other thing to note is that, because PWAs aren’t mobile applications, they don’t have access to the full extent of native platform functionality that a mobile application would have. So, where a mobile application can leverage the device for alarms, phonebook access, and various hardware sensors, PWAs do not have access to these features.

The value of PWAs

Some of the value of PWAs are apparent from the above paragraphs, but let’s break those down a little more and add a few as well.

Platform Independent

Despite Apple’s current lack of support, PWAs are designed to work independently of what mobile platform it’s on. What this means for the end user is that the PWA will look and act the same, and work, no matter what mobile platform they choose to use.

The benefits are pretty significant for the company publishing the PWA as well. Developing a mobile application for your entire audience meant nearly full development life cycles for multiple versions. Even though the requirements might be the same, divergent apps needed to be developed, tested, deployed, and maintained. For a company with a dedicated development team, it meant additional headcount just for mobile application support. For those without it, it resulted in contracts for initial app development as well as updates.

Offline Availability

PWAs were specifically designed to handle questionable or unstable network conditions. The idea was to ensure that the user could use the application regardless of their current network access. PWAs use caching as well as code called Service Workers that act as the proxy intercepting and responding to network requests.  

User Re-engagement

Push notifications have been proven to increase user re-engagement in mobile applications. But mobile web experiences didn’t have the ability to recapture the interest of the user.

Since PWAs are a hybrid mobile web experience and mobile application, they can use push notifications to return the user’s attention to your content and functionality. Users who enable push notifications are more engaged, have better retention and have great app usage longevity that those without the notifications.

Full Screen and Splash Screen

It was always clear that a web page on a mobile device was just that – a web page on a mobile device. But PWAs allow for a more mobile application type feel thanks to the use splash screens. And because PWAs are full screen, just like a native mobile application, it’s hard to tell one from the other.


Being visible on a mobile search is becoming increasingly important. Mobile friendly web pages receive special attention from Google, too. But this is an area where native applications fall short of web pages, with little or no SEO pull beyond promotional pages for the app. PWAs, on the other hand, can be easily indexed by search engines.

Responsive websites aren’t going away today, and there are still valid business cases for mobile applications, especially ones that require certain mobile device functionality. But, if experts like those at Gartner and Google are to be believed, PWAs will be the new standard in web interactions.