What Is a Progressive Web Application?


Progressive web applications (or PWAs) are gaining popularity as smoother, more streamlined alternatives to native apps. But what exactly is a PWA, and why do Front-End Developers love them so much?

In this article, we’ll explore the answers to these questions as well as how to get started with learning to develop a PWA.

What is a progressive web app?

A progressive web app is a kind of application software that’s designed to work on standard browsers like Chrome, Safari, Firefox, and Edge.

Basically, PWAs look and feel like a “normal” app that you’d download to your phone or tablet. But, they’re accessed through your browser, so they’re developed using HTML, CSS, and JavaScript rather than more traditional app-development languages like Swift or Kotlin.

As you can imagine, there are some big drawbacks to browser-based web apps, such as the need to stay connected to the internet. PWAs allow developers to overcome some of these disadvantages to create apps that combine the ease of web apps with the seamless experience of an installed native app.

What key principles make an app a PWA?

Think of PWAs as an approach to creating apps rather than a specific app technology or programming language. Below are some key principles that developers follow when creating a PWA.


PWAs are fully accessible within a web browser and can be found using a search engine. Note that this isn’t the same as searching for a native app using a search engine, which leads you to a page to install the app rather than the app itself.

Some PWAs are discoverable on app stores like the Google Play Store or Apple’s App Store, but this isn’t a defining principle of PWAs. In fact, many PWA developers prefer to avoid the approval process and contractual requirements that come with adding an app to one of the app stores.


To bring a “native app feel” to a PWA, many developers allow their PWAs to be added to a device’s home screen for easy access. This isn’t quite the same as installing a native app, which takes up storage space on the device. Instead, a PWA icon is more like a browser bookmark that takes you straight to the PWA site in your browser.

Rather than being a necessity, installing a PWA is a convenience for anyone who likes the app and wants to keep using it.


Since PWAs live on the web, they can be accessed with a unique link. This makes them easy to share through messaging or social media without involving an app store or installation process.

Network independence

This is where PWAs really start to shine. One of the biggest disadvantages to browser-based content is that everything falls apart when there’s no internet connectivity. PWAs use a variety of tools to overcome this major obstacle and provide a better user experience when you’re in the subway or on Airplane Mode.

Using technologies like Service Workers, Cache API, and Web Storage API, PWAs can store app information that you’ve recently accessed. That way, if you navigate back to a previous page, you can see what you already loaded instead of getting the dreaded “currently offline” page. When you’ve connected again, PWAs can seamlessly update content and manage your network requests.


Re-engageability is a fancy term for “notification and update support.” PWAs use tools such as Notifications API and Web Push API to update content in the background, so you’re always looking at the most up-to-date information when you pick up your device. Notification sounds, badges, and banners are also supported so that you know when there’s something new to review.

Responsive design

PWAs are designed to look great on various devices, including phones, tablets, and desktop browsers. The user interface can be automatically resized when you rotate your screen or change resolution.


Have you ever looked for a particular app in an app store, only to find several apps that all look the same? Unless you’re ready to do some research, it can be hard to determine which app developers are the real deal and which ones are pushing look-alikes.

PWAs help clear up a lot of confusion because all apps are tied to a URL. So, it’s possible to apply the same rules for safe browsing to PWAs — sticking to those that use HTTPS protocol and incorporate the company’s official URL.

Why use a PWA?

By now, you’ve learned about the key features of PWAs — but don’t native apps have a lot of the same features? The answer is yes, but PWAs offer a few distinct advantages that make them so attractive.

No installation needed

While PWAs can be added to your device’s home screen, there’s no need to go through the download and installation process. As long as you have the PWA’s link, you can start using it immediately. This is particularly convenient if you only need a PWA temporarily or infrequently.

Lower storage requirements

Since PWAs live on the web, they take up far less room on your device than installed native apps. And, while many PWAs store information for offline access, they’re still far less space-intensive than comparable native apps. For example, Starbucks offers a PWA that’s over 99% smaller than its native iOS app.

Instant updates

The best thing about PWA updates is that you never have to worry about them. Rather than downloading and installing updates, PWAs are updated as soon as you refresh the page.

More app interaction

The result of all of the above advantages of PWAs is that people are more likely to use them compared to a native app. So, they’re also likely to spend more time on a PWA.

This is why so many tech companies spend as much time — if not more time — on PWA development and maintenance as they do on their native apps.

How do you start developing PWAs?

If you’re starting a new career as a developer, particularly as a Front-End Developer, then it’s worth knowing the languages behind PWAs. These include:

If you’d rather learn how to use all these tools at once, check out our Front-End Engineer Career Path! While learning how to build your own websites, you’ll also build a portfolio that’ll help you impress future employers and clients. We’ll even help you prepare for upcoming interviews.So, what are you waiting for? Sign up today!

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