A website that can be downloaded to your device and used like an app is known as a progressive web application (PWA). A PWA is the NIOSH Hearing Loss Simulator, for instance. A PWA can be installed and used just like a standard web page, but it also has several benefits. Without an internet connection, a PWA that has been deployed is still functional. For ease of access, it will also show up with your other apps.
In exchange for some freedom, progressive web apps allow websites to operate more like native mobile apps. Without all the hassle of app store approvals and copious amounts of platform-specific native code, you get native mobile app capability (or something very close to it). A progressive web app can be installed on a user’s home screen and used the same way as a native app. The progressive web app is nevertheless launched under a pseudo-app frame that has some limitations and only permits access to pages that are sub-paths of the progressive web app’s original path. They must also be delivered via HTTPS.
The service worker, which is essentially a client-side JavaScript daemon, is the heart of a progressive online application. Employees in the service industry can listen for certain occurrences and respond to them. The fetch event, which may be used to cache web content offline as will be explained below, is one of the most often supported events.
The guidelines and limitations of progressive web apps are perfectly appropriate for many websites. Progressive web app updates are fetched by a service worker adhering to conventional HTTP caching guidelines, as opposed to waiting for Apple or Google to authorize and push out native app updates. Plus, progressive web apps can now use many native APIs like the geolocation, camera, and sensor APIs that only native mobile apps used to be able to take advantage of.
The installation procedure differs based on your web browser and operating system.
Installing a PWA on iOS
A PWA can only be installed on iOS using the Safari web browser. First, navigate to the site in Safari. Press the “Share” button and select “Add to Home Screen” from the popup. Lastly, tap “Add” in the top right corner to finish installing the PWA. It will now be on your home screen.
![Screenshots of the iOS PWA installation process.](https://i0.wp.com/www.cdc.gov/niosh/mining/UserFiles/content/hearingloss/images/pwa_ios.png?resize=640%2C445&ssl=1)
Installing a PWA on Android
The default Chrome browser is capable of installing PWAs for Android. First, navigate to the site in Chrome. Press the “three dot” icon in the upper right to open the menu. Select “Add to Home screen.” Press the “Add” button in the popup. The PWA is now installed and available on your home screen.
![Screenshots of the Android PWA installation process.](https://i0.wp.com/www.cdc.gov/niosh/mining/UserFiles/content/hearingloss/images/pwa_android.png?resize=640%2C450&ssl=1)
Installing a PWA on a Windows PC or Mac
Google Chrome and Microsoft Edge currently have the best support for PWAs on Windows and Mac OS. The installation process is very similar for both browsers. First, navigate to the site you wish to install as a PWA. If the site is a PWA, there will be an icon on the right side of the URL bar. Click the icon then click the “Install” button. Alternatively, you can install the PWA from the “three dot” menu.
Read Also: How do You Monetize PWA?
On a Windows PC, the PWA will be available in the start menu. On a Mac, the PWA will be in the launcher and in the spotlight search.
Microsoft Edge
![A screenshot of the installation process in Microsoft Edge.](https://i0.wp.com/www.cdc.gov/niosh/mining/UserFiles/content/hearingloss/images/pwa_edge.png?resize=595%2C267&ssl=1)
Google Chrome
![A screenshot of the installation process in Google Chrome.](https://i0.wp.com/www.cdc.gov/niosh/mining/UserFiles/content/hearingloss/images/pwa_chrome.png?resize=619%2C251&ssl=1)
Go to the website you wish to add as an app on iOS Safari and hit the share button. On the sharing sheet, click the “Add to Home Screen” button. The progressive web app’s URL starting page can be named and modified in the following dialog box before it is placed to the home screen. Then you may use it just like any other program, launch, control, and delete it.
When using Chrome on an Android device, tap the hamburger menu in the top right corner of the browser window, then tap “Add to Home screen.” You could be asked to confirm before it places the icon on your homescreen for you to use, multitask with, or remove just like any other app. Unlike iOS, you cannot edit the starting URL or name of a progressive web app with Android.
PWAs are at their core performance-based. Users should be able to access your software quickly regardless of the network. Although caching and offline functionality are very helpful, your application should still load quickly even if the user’s browser does not support service worker technologies. Providing a wonderful experience for everyone, independent of device modernity or network conditions, is the definition of progressive enhancement.
The RAIL system is a valuable set of measures for doing this. RAIL is a set of standards for evaluating the performance of our app that Google refers to as a “user-centric performance model.” The acronym stands for Response (how long it takes for your app to respond to user actions), Animation (keeping animation speed at 60fps), Idle (using time when your app isn’t doing anything else to load and cache additional assets) and Load (loading your app in one second or less).
Audit your app with Lighthouse
The company supporting Progressive Web Apps as the web’s future is Google. As a result, it has provided a helpful tool for directing the growth of your PWA.
With Chrome 60, it was formerly known as Lighthouse and was offered as a Chrome Extension. It is now found in the Chrome DevTools on the ‘Audits’ page. Lighthouse tests your application in several scenarios and evaluates its performance in accordance with PWA standards. After that, you are given a score out of 100. At the same time, it can rate your application according to web best practices.
The following text is a list of the values Lighthouse measured. In use also shows descriptions.
- Registers a Service Worker
- Responds with a 200 when offline
- Contains some content when JavaScript is not available
- Uses HTTPS
- Redirects HTTP traffic to HTTPS
- Page load is fast enough on 3G
- User can be prompted to install the Web App
- Configured for a custom splash screen
- Address bar matches brand colours
- Has a <meta name=”viewport”> tag with width or initial-scale
- Content is sized correctly for the viewport
The result of all these procedures is a progressive web application. Users’ loaded content will automatically be cached for later offline access. It will be fascinating to watch how service industry professionals change over time.