Beginners Guide to Develop a Progressive Web App

Progressive Web Application

The entire world is going mobile. Even enterprises are bringing in enterprise mobility and putting mobile strategies first to operate and deliver results. With this dynamic rift in the way we consume content and the medium we use for it, there has been a demand for optimum customer experience.

Brands and businesses want to gain the attention of their target audiences and keep them captivated with unique content and notifications. While rolling out dedicated apps for this purpose does sound like a plan, the reality is that users have way too many apps installed and abandoned after single use.

So, how do businesses tackle this concern and yet manage to engage with customers?

Well, progressive web application development is the solution. In this post, we will understand what progressive web app development is, learn its anatomy and more interesting details about it.

Here we go.

What is A Progressive Web Application?

A progressive web application is an application software delivered through the web and also run as a native app known as PWA. It offers the advantages of both web and native apps. Furthermore, it is possible to develop it using specific standards and technologies.

PWAs can be just published online with just Add to home screen feature so that users can also install the application. Note that publishing a PWA on the Apple store or Google store is optional.

How Do You Know If An Application Is A PWA?

An app is considered a PWA when it has a set of features. For instance, it should work offline, is installable on portable devices, is easy to synchronize, compatible with push notifications, and more.

There are some key principles a web app should have to become a PWA.

  • It should be Discoverable so it can be foundthrough search engines like Google.
  • It should be Installable so it can be added in a user’s home screen for further use.
  • Users should be able to share the link of a progressive web app to anyone.
  • It should also work offline or with poor network connection.
  • It should be progressive so that it is usable on old older browsers and can be fully functional on the latest ones. 
  • It should be re-engageable so it is able to send push notifications.
  • It should be responsive so that it can look good on all devices with a screen and a browser. 
  • It should be secure so the connections between the user, the app, and your server are secured against any third parties.

Success Stories of PWA

The most known success story of PWA is Flipkart Lite. India’s largest e-commerce site has been rebuilt as a progressive web app so that it can have a 70% increase in conversions.

The Anatomy Of A PWA

There are two main approaches for rendering a website:

  • Server-side rendering (SSR)
  • Client-side rendering (CSR)

They both have their own advantages and disadvantages, and you can mix the two approaches.

Server-side rendering (SSR):

A website is rendered on the server so that it can load quicker but when it navigates between pages, it requires downloading new HTML connect.  It works well across browsers but it is time consuming when navigating between pages because loading a page requires a new round of trip to the server.

Client-side rendering (CSR):

This allows the website to be updated in the browser almost instantly when navigating to different pages but requires more of an initial download hit and extra rendering on the client side at the beginning. The website is slower on an initial visit but can be faster to navigate.

The best popular approach is the app shell concept, which uses both SSR and CSR.

The app shell concept caches the contact as soon as possible so it’s available offline and when next time someone visits the app from the device, the UI loads from the cache and requests a server for another connection. 

Sample Structure Of A Progressive Web Application

Add to Home screen feature

The Add to Home screen feature is available in the latest browsers that allow users to install a web app into their device so that they can access it with a single tap rather than visit the website URL. It is the best feature when using a web app very frequently. 

PWAs Work Offline With Service Workers

  • Service workers are used to cache the assets of a website so that they can load websites offline or with the poor network. It is a virtual proxy between a browser and a network.
  • They run on separate threads from the main JS code and don’t have any access to the DOM structure. It is a different approach from traditional web programming. The API is non-blocking and it is a communication bridge between different contexts. You can receive the result whenever it is ready using the async approach.
  • They can do a lot more than “just” offering offline capabilities, including handling notifications, performing heavy calculations on a separate thread, etc. Service workers are quite powerful as they can take control over network requests, modify them, serve custom responses retrieved from the cache, or synthesize responses completely.
  • It’s not only about offline support but it provides more features like handling notifications, performing heavy calculations on a separate thread, etc. Service workers are powerful because they have control over network requests, modify them, serve custom responses retrieved from the cache, or synthesize responses completely.

Registering the Service Worker

if('serviceWorker' in navigator) {
  		navigator.serviceWorker.register('./examples/kw.js');
};

If the service worker API is supported in the browser, it is registered against the site using the ServiceWorkerContainer.register() method. Its contents reside in the kw.js file and can be executed after the registration is successful.

PWAs Are Re-engageable Using Notifications and Push.

  • Push and Notifications are two different APIs. They work together when you want to provide engaging functionality in your app.
  • Push is used to provide new content from server to the app without any client-side interruption.
  • Notifications can be used to show new updates to users when something has been updated and it is used by service workers.
  • When an app’s page is out of focus or closed the updates can be pushed and notifications can be shown because they work outside of the browsers.

Progressive Web Apps with and without frameworks

  • Many open-source Progressive Web Apps have already been built with and without JS libraries and frameworks. You can see the below examples of PWAs. They are pretty good apps.

Wrapping Up

Progressive Web Apps are still in their infancy but it’s an exciting time to play around with the methodologies behind them and see how well they can apply to your own web apps.

However, if you feel developing a PWA is too tedious and you don’t have the right strategy or direction to go ahead with it, simply reach out to DEV IT. We will help you to develop and launch the PWA your market segment deserves.