How to Build Progressive Web Apps (PWAs)

If you’re in the software development world, I’m sure you’ve heard of progressive web apps, aka PWAs. That’s because PWAs are now too big to ignore, bringing numerous benefits when it comes to increasing user engagement and retention. One thing that you may not know is how easy it is to build progressive web apps, and that’s exactly what we’ll cover here.

In an era where customer experience is king, businesses need to find ways to go that extra mile to make their customers choose them over a competitor. And that’s where PWAs come in, as a new way of distributing apps, providing users with frictionless experiences. Let’s quickly recap what PWAs are all about before moving to how easily you can start building your own.

What is a PWA?

PWAs combine the functions of native apps and website accessibility, all while not requiring any app store involvement. Like native apps, PWAs can work offline, send push notifications, and access device hardware, such as cameras or GPS. This allows you to create user experiences similar to native apps on mobile and desktop devices.

But unlike native apps, PWAs are built using standard web technologies such as HTML, CSS, and JavaScript. This means that you won’t need to resort to native mobile-specific development teams, which massively reduces both the time and cost required to build them. Additionally, with PWAs, you’ll experience:

• Faster development and reduced maintenance costs: Since PWAs are mobile-optimized versions of web pages, you have one codebase for all devices.
• Easier deployment: PWAs don’t need to go through the process of distribution through the app stores. So, whenever you need to update your app to fix a bug, for example, you don’t need to wait for those changes to be approved by the app store. This way, you can get that new version out much faster.
• Broader reach: PWAs are searchable by search engines, making them easier to find.
• Reduced customer friction: Because the user doesn’t have to go through the hassle of downloading the app from the app store, they’re more likely to download a PWA than a native app. Plus, PWAs also have a smaller size (often under 1MB), making the download much faster while taking less space on the user’s phone. Thus, you’re able to increase customer engagement and reduce waiting times.

If you want to learn more about the benefits of PWAs and when you should choose them over native apps, here’s a great article about the topic.

How Does a PWA Work?

We’ve seen what PWAs are and how they apply to the real world. But from a technical perspective, what’s happening there? A PWA is an app served over a secure connection by service workers and assisted by a manifest.json file. Confused? No need to be.

A service worker is a simple file that allows the PWA to store HTML, CSS, and images in the browser cache to show them even if there’s no network connection. The JSON file is a storage for the app’s information. This is everything you see when accessing the app on your phone’s main screen. Finally, a secure connection allows everything else to work together, both online and offline.

Apparently, there’s not much complexity when we check what’s going on in the PWA backstage. However, the amount of allowed customization also appeals to those who want to dive deeper into it.

Building Progressive Web Apps

Imagine you work in the IT department of an airport inspection company. Airports hire your company to ensure that taking off and landing of planes is done safely, which includes a set of complex tasks. To improve work efficiency, your boss asked you to develop an inspection app that allows field inspectors to register the condition of common safety concerns at the airport. This app must:

• Allow field workers to take pictures on the runway
• Access the device’s GPS
• Work offline because the inspectors might not have internet access when they’re in the field
• Work on multiple devices

In this case, a PWA is the best solution. Even if you need to make a change later, you can iterate your PWA, and everyone will get the new version with no app store involved. Here’s an example of a PWA that you could build for this scenario.

And what if I told you that all it takes to turn your app into a PWA is switching a toggle? In OutSystems it’s really that simple. Our low-code platform will automatically generate all the needed resources and turn your app into a PWA when you enable PWA distribution. After this simple step, you’ll be ready to deploy it to your end-users. Sign up for a free personal environment and see for yourself how easy it is.

Take that airport app we’ve created as an example. It’s a PWA with four screens that access the device’s camera and GPS, with offline and sync functionalities, built with OutSystems. It took just 19 minutes of development time to get it done from scratch. Curious how? Check out the full webinar in How to Build Progressive Web Apps Using OutSystems.