Following a rise in the popularity of smartphone usage over conventional computers, there's an emergent trend in web development centered around creating app-like experiences for websites through what are collectively known as progressive web apps. Colloquially called PWAs, these are effectively websites that act like mobile applications and can even be installed on a smartphone home screen for easy access. They don't even require the internet to run, even if they do require a connection every once in a while to update information and other aspects of the site. Instead, all of the required data is effectively cached on a given handset or tablet directly behind the same kinds of icons more generally associated with standard apps a user might download from the Google Play Store. That doesn't mean there aren't differences between the two types of applications. However, with support from tech and web giants such as Google, Mozilla, Microsoft, and even Apple, PWAs are quickly becoming the de facto standard for accessing web content on less stationary browsing devices.
Defining what progressive web apps are is straightforward enough and the reasons they are growing in popularity so quickly is not difficult to work out. After all, mobile handsets, tablets, and even Chromebooks have fundamentally changed what it means to have an intuitive and fulfilling interaction with content across the board. That's true whether a user needs to pay bills, access their banks, rent or watch a movie, perform document editing or file format conversions, navigate for a road trip, or just keep up with the news that's important to them. Almost nobody wants to return to the clunky, slow experiences on offer in the past. Bearing that in mind, PWA goes quite a bit further than that in that they are generally universal. They'll work in nearly any web browser just like a traditional website, without developers needing to code a different iteration for individual devices or web environments. That's through the use of Cache API and IndexedDB, which effectively cache the website in its entirety to a given device. That's a completely different approach than Google's Web Apps, found in the Chrome Web Store, or even Microsoft's app market, both of which require a dedicated environment to work in. Meanwhile, other underlying technologies such as Fetch API allow those cached variants to be updated in the background when a connection is available and as the site is updated. Dedicated Web App Manifest files allow for icons that are scalable to suit the device in question and they are encrypted via HTTPS for security.
Depending on where they're installed, dedicated icons are generated on the home screen, in the taskbar, or on the desktop. Among the most readily available example of one way this can be incorporated is seen in Firefox 58 and up for Android, which was released back in October. The browser actually has a dedicated option for creating a cached version of any website on the home screen of any Android device. Since those pages are cached, they load quickly and function almost completely without lag or other similar problems often associated with bigger sites. That does mean that they can take up a comparatively large amount of space, but one of the perks of PWAs is that they can be uninstalled and reinstalled with relative ease, just like a standard application. They'll load with equal rapidity regardless of whether the user's device is actually connected to the internet, though a lacking connection would present obvious problems for web apps associated with real-time functions such as a banking website. With that said, that approach is actually fairly rudimentary compared to what could be done with progressive web apps in the future.
They'll even run smoother and more quickly than many standard dedicated apps depending on their use. That's because web apps can actually be installed like any other application and developers behind the websites in question can create experiences that are much more closely related to a truly immersive mobile application experience specifically downloadable for users who want to take advantage of those. Progressive web apps open in their own dedicated windows and are rescaled to suit the device they are run on, just like mobile applications. In fact, it isn't just web developers working to bring PWAs to users, though websites can be retrofitted easily enough. Smartphone and computer application developers are also working to take advantage of the benefits since it eliminates multiple variations or ports of an application and can serve a similar functionality. Moreover, updates can be pushed on the server side so that end-users can effectively update the app just by connecting to the internet and opening the web app. The site & app will then update to the latest version, pulled and synced from the server, instead of having to download a whole new APK and go through the installation process all over again. That's suitable for a huge number of applications on mobile handsets and could even be used in apps associated with services like Netflix or Hulu effectively. Since PWAs can also be listed in various app stores or downloadable from website's directly, they also open up a huge possibility in terms of reaching wider audiences without requiring users to rely on the current application sources – although that would always remain an option.
Of course, it most likely won't work with the vast majority of mobile games or similarly high-intensity applications, but that isn't really the point. Instead, the purpose here is to drastically reduce the number of resources required to interact with some of the most popular tasks accomplished on smartphones and computers, as well as eliminating the various issues that can arise when trying to navigate those from a standard web browser. Given the breadth of functionality, PWAs can offer, in combination with how easy they are to generate – only requiring open, standard W3C web technologies and a single development process – this is almost certainly going to remain a trend going forward. It may just be that the usefulness of progressive web apps over standard applications results in their eventually overtaking the currently much more common dedicated application since the majority of applications could arguably take advantage of the improvements on offer.