The Ultimate Guide to Progressive Web Applications (PWAs): What, Why, How & When

In the modern web development landscape, Progressive Web Applications (PWAs) have gained immense popularity due to their ability to bridge the gap between web and mobile applications. Whether you're a fresher looking to learn PWAs or a developer seeking to enhance your skill set, this guide will cover everything from the history and benefits to the technologies and steps required to build a PWA.

What is a Progressive Web Application (PWA)?

A Progressive Web Application (PWA) is a type of web application that provides an app-like experience using modern web technologies. PWAs can work offline, send push notifications, and be installed on a user’s home screen without requiring an app store.

Key Features of PWAs:

• Responsive & Adaptive – Works across devices of different screen sizes.
• Offline Support – Uses service workers to cache content and work offline.
• Installable – Can be added to the home screen like a native app.
• Fast & Engaging – Loads quickly and delivers a smooth user experience.
• Secure – Served over HTTPS to ensure security.
• Push Notifications – Allows re-engagement with users like mobile apps.

Why Choose PWAs?

PWAs have revolutionized how web applications function by merging the best of web and mobile apps. Here’s why businesses and developers prefer PWAs:

• Faster Load Times: PWAs use caching mechanisms to deliver content quickly.
• Better User Engagement: With push notifications, PWAs increase retention rates.
• Lower Development Cost: Instead of developing separate native apps for Android and iOS, a single PWA works across all platforms.
• Offline Capabilities: Users can access key features even without an internet connection.
• SEO Friendly: Unlike native apps, PWAs are indexable by search engines, improving visibility.

The Purpose of PWAs

The ecommerce world is evolving rapidly, and mobile-first ecommerce has been the standard for years. PWAs play a crucial role in this transformation by enhancing user experiences and accessibility. Here are some key statistics that highlight their importance:

• Global mobile users surpassed desktop users for the first time in 2014 (comScore).
• By 2025, retail mobile commerce sales are projected to reach $728.28 billion and account for 44.2% of retail ecommerce sales in the US (Business Insider).
• 80% of shoppers use a mobile phone inside a physical store to look up product reviews, compare prices, or find alternative store locations (Outerbox Design).

These numbers emphasize the need for businesses to adopt PWAs to stay competitive in the digital marketplace.

A Brief History of PWAs

Google is the godfather of PWA, which should come as no surprise. PWA, by blending the web- and mobile-like UX, has a chance to break down the wall in the garden of data guarded by Google and Apple. While Google can afford that (as its data storage also contains pretty much all of the world wide web), Apple is not in such a comfortable position here.

However, the idea of putting mobile user experiences in the center of interest was actually put forward by Steve Jobs over a decade ago. Apple’s CEO presented the concept during the iPhone introduction in 2007 because, at the beginning of the mobile revolution, it seemed obvious that external apps would be a way to leverage the popularity of the nascent Apple device. Jobs wanted to encourage developers to build them.

That was, however, a short-lived idea. In July 2008, Apple placed the concept of "universal apps" on ice. The company presented the App Store instead, and mobile apps started to dominate the internet.

The PWA-specific approach had to wait for its moment, which came a decade later. In 2015, Frances Berriman and Alex Russell, the authors of the term PWA, wrote in the foreword of “Progressive Web Apps,” a book by Jason Grigsby:

"The idea of native apps always seemed like a regression. Walled gardens with terrible search, dubious security, and the endless tax of updates - it felt so 1990s."

Berriman and Russell noticed a new type of website delivering a way better user experience than traditional web apps. They called them “Progressive Web Apps.” A year later, during the Google IO conference, Eric Bidelman, Senior Staff Developers Programs Engineer, introduced Progressive Web Apps as a new standard in web development.

In early 2018, Apple shipped support for basic features of PWA but still imposed certain limitations regarding cache capacity or native push notifications.Technologies Used in PWAs

To build a PWA, you need to understand and use the following technologies:

1. HTML, CSS, and JavaScript – The foundation of any web application.
2. Service Workers – JavaScript scripts that run in the background, handling caching and offline functionality.
3. Web App Manifest – A JSON file that defines how the PWA should behave when installed on a device.
4. HTTPS – Ensures secure communication.
5. IndexedDB or Cache API – Used for storing data offline.
6. Frameworks & Libraries: While PWAs can be built using vanilla JavaScript, frameworks like React, Angular, and Vue.js provide better structure and efficiency.

What Should a Fresher Do to Learn PWAs?

If you're a beginner, follow these steps to master PWAs:

1. Learn HTML, CSS, and JavaScript – Strong foundational knowledge is essential.
2. Understand Service Workers & Web App Manifests – Study their role in PWAs.
3. Experiment with Simple PWA Projects – Try building a small to-do list app with offline functionality.
4. Follow Tutorials & Documentation – Google Developers, MDN Web Docs, and YouTube have great resources.
5. Work on Real Projects – Contribute to open-source projects or build your own portfolio PWA.

Real-World Examples of PWA Success

Progressive Web Apps have delivered outstanding results for various businesses worldwide. Here are some key success stories:

• Best Western Hotels saw a 300% increase in revenue after adopting a PWA.
• Forbes.com experienced a 100% increase in user engagement with their PWA.
• AliExpress observed a 74% increase in time spent on their platform.
• Flipkart achieved a 70% increase in conversion rate.
• MakeMyTrip.com recorded a 3X boost in conversion rates.
• Wego saw a 3X increase in ad click-through rates.

Case Study: Foodl – B2B Online Marketplace

Foodl, an online marketplace for the HoReCa industry, needed a flexible digital solution that didn’t force users into a restrictive experience. By adopting a PWA, they achieved:

• Seamless user journeys across devices and channels.
• Faster time-to-market.
• A scalable architecture for future growth.

Case Study: Garten-und-Freizeit

Raumschmiede, the company behind Garten-und-Freizeit, needed a fast and responsive solution to manage over 30,000 products. Their PWA delivered:

• A 350% increase in active monthly users.
• A 630% boost in organic search traffic.
• A 39% decrease in bounce rates.

Free Learning Resources for PWAs

1. Google Developers – PWA Documentation
2. MDN Web Docs – PWA Guide
3. FreeCodeCamp – PWA Crash Course
4. Web.dev – Service Workers
5. Udemy – Free PWA Course
6. PWA Roadmap – roadmap.sh
7. YouTube – Academind PWA Tutorial
8. Google Codelabs – PWA Hands-on
9. The PWA Book (Free Online)
10. Dev.to – PWA Tutorials & Blogs