How to Excell in Progressive-Web Apps – Top 3 Technologies

What are Progressive-Web Apps (PWA)

Google announced PWA technology in 2015. It positions itself as an additional add-on that allows you to make the site look like a mobile application.

Progressive Web App or PWA is the best way for developers to make their web apps load faster and perform better. PWAs are websites that use modern web standards, making installing them on a user’s computer or device possible. In operation, they are like applications. The most famous example is Twitter, which launched mobile.twitter.com as a PWA powered by React and Node.js.

PWA is a web application that can be installed on your system. It works offline when there is no internet connection, making the most of the data cached the last time you used the app. If you access the site from Chrome on a desktop and have the appropriate flags enabled, you will be asked to install the application.

PWA or Progressive Web App comes from technical jargon but is the next step in user-friendly apps. Application developers should take a closer look at them.

They combine the convenience and appearance of the application while developing them is as easy as a regular website. These modern applications provide access to your content and a first-class service that makes users happier.

Progressive apps can be called responsive sites because they adapt to the capabilities of the user’s browser. They can automatically improve the browser’s built-in features so that the site experience is similar to that of a native web application. Basic PWA components:

1. Web application manifest: to provide native functionality such as an application icon on the desktop;
2. Service Worker’s technology: for background tasks and offline work;
3. Application shell architecture: for fast loading with Service Workers.

The most popular PWA use cases are Alibaba, Forbes, The Weather Channel, and MakeMyTrip.

PWAs help solve issues such as slow internet speeds, long website loading times, and interactivity. This is a good reason to use Progressive Web Apps. Here are some of the main features that PWAs provide:

1. Speed. PWAs always load quickly. From the moment a user downloads an app to the moment they start using it, everything happens incredibly fast. You can also promptly re-launch the application without a network connection.
2. Reliability. Thanks to Service Workers technology, you can fully load the image on the user’s screen, even if the Internet is turned off.
3. Integration. With PWA, everything loads smoothly and seamlessly. The app resides on the user’s device, sends push notifications, and accesses features like native apps.
4. Interactivity. Since we can send notifications to the user, we can increase his interest and involve him in working with the application.

We will consider three of the most popular technologies used in PWA, Angular, React, and Lit, and how they help the development.

Angular

Angular is a JavaScript framework. The library helps to create web applications – sites that load only once. This technology has a fairly low entry threshold, so it often becomes the next logical step after learning JS. The value of such specialists is greatly increased – a person’s opportunities are expanding, and the understanding is fixed that programming is about constant learning and development.

Building applications with Angular JS is a promising direction and continues to gain popularity, so choosing it as the next milestone in development is a good decision.

The angular developer is a sought-after profession as more and more companies want to use this technology. Google supports the framework; it is used in Google mail and YouTube applications. Such companies have already been chosen as Lego, PayPal, and Upwork.

Angular is more suitable for large projects with a rigid structure. It has a lot of ready-made solutions and a more intelligent system for collecting and storing information. This simplifies the construction of large websites and ensures that they function reliably.

You can use Angular for both hybrid and SPA applications. The latter are one-page sites designed so that the user does not download new information by going to the pseudo-page. Only dynamic data is updated. Loading is necessary only once, regardless of which pseudo-page the user got to first. On standard sites, each new page is pulled up separately – people with a poor-quality Internet connection are forced to wait, watching a blank screen, skeletons, or a preloader.

A new generation of SPA applications, PWAs, are being created so that the site can work offline. They can be downloaded quite easily on a smartphone. This is indeed possible, and Angular is used for this. It should be borne in mind that such a product cannot load dynamic data. The user will freely work with the content already present on the device. But SPA and PWA are far from all that can be done with Angular.

Angular can build PWAs by leveraging its capabilities to create responsive, scalable, high-performing web applications. Here are some ways Angular can be used in PWA development:

1. Service Workers: Angular supports service workers, a key component of PWAs. Service workers allow for offline caching, push notifications, and background syncing, which can significantly enhance the user experience. With Angular, you can easily configure and use service workers to make your PWA work offline and load faster.
2. Responsive Design: PWAs must be responsive to fit different screen sizes and device types. Angular provides powerful layout and design capabilities that allow for the creation of responsive user interfaces. With Angular Material, you can create beautiful, responsive UI components that work seamlessly on desktop and mobile devices.
3. Progressive Enhancement: Progressive enhancement is a key principle of PWA development, which involves designing web applications to work even in less-capable environments. Angular allows you to build PWAs that progressively enhance functionality based on the user’s device capabilities. For instance, you can use Angular’s lazy loading and conditional rendering capabilities to load only the necessary parts of your application based on the user’s device and network conditions.
4. Offline Capabilities: PWAs need to work offline or with limited network connectivity. Angular supports offline data storage through technologies such as IndexedDB and Web Storage. You can use these technologies to store data locally on the user’s device and sync it with the server when a network connection is available.

React

React is a product of Facebook. It is a flexible and efficient JS library for creating interactive user interfaces. React builds the presentation layer of a web application, which is technically the front end. This allows you to build applications with useful features such as reusable components, state management, partial DOM rendering, etc. React is mainly used to create single-page applications (Single Page Applications, SPA).

React allows you to use components – independent and reusable pieces of code. In other words, components are functions that work in isolation; each component has its state that can be controlled. This greatly simplifies the creation of large applications since individual blocks of code do not depend on each other, and breaking one does not affect others.

When making changes to the DOM, the virtual DOM is first changed, then the virtual and original DOM are compared, and changes are made only to that part of the actual DOM that differs from the virtual DOM. This greatly improves the application’s performance because changes do not result in a page refresh.

Designing any view in React is easy, and these views allow you to manage their state. React allows you to render individual components, which makes code maintenance and troubleshooting easier.

React is very fast. The virtual DOM ensures that the original DOM is only re-rendered when necessary. In addition, React uses one-way binding (one-way data flow), a Flux design pattern. This makes components immutable (immutable), providing more flexibility and efficiency. JSX is a combination of JavaScript logic and HTML/XML markup. It is used to create components. Such files have the .jsx extension.

Unlike other frameworks like Angular or VueJS, React is easy to learn and use. With basic knowledge of HTML, CSS, and JavaScript, you can get started with React.

React is very easy to use. We have several powerful packages for building projects, such as Webpack. With a few simple JSXs, you get components that are rendered separately. React becomes even more powerful when combined with other libraries like Redux, Material-UI, Materialize, GraphQL, etc.

React is the most popular library among developers. It is open source, and many people are working on it. Its repository contains 150 thousand stars, and the number of downloads is approaching 4 million.

React is also used in mobile development. React Native is used for this. This shows React’s flexibility in terms of adaptability. With React, a developer can create Android, iOS, and web apps.

React’s support for service workers, app shell architecture, responsive design, code splitting, and offline data storage make it a great choice for building PWAs that deliver a fast, reliable, and engaging user experience. Here are some more details about how React can be used in building PWAs:

1. Service Workers: React provides a simple and effective way to add service workers to a PWA using its built-in service worker API. This allows you to cache assets and data for offline use easily and provides the ability to receive push notifications and perform background syncs. Additionally, libraries such as workbox and sw-precache-webpack-plugin can further simplify the configuration of service workers in a React app.
2. App Shell: A key concept in PWA development is the app shell, which is the minimal HTML, CSS, and JavaScript required to load a user interface. React’s component-based architecture makes it easy to create reusable and modular UI components that can be combined to form the app shell. This approach can lead to faster load times, improved performance, and better maintainability and code organization.
3. Responsive Design: React can be used with CSS frameworks such as Bootstrap or Material-UI to build responsive UI components that work well on different screen sizes and device types. React’s react-responsive library can conditionally render elements based on the user’s screen size or device orientation.
4. Code Splitting: React’s support for code splitting allows for creating of smaller, more efficient JavaScript bundles that can be loaded on demand. This is particularly useful for PWAs, as it allows for faster initial load times and improved performance on slower networks.
5. Offline Data Storage: React can be used with libraries such as redux-persist or localForage to store data offline using IndexedDB or Web Storage. This allows for improved app performance and functionality when the user is offline or has limited network connectivity.

Lit

Lit is a lightweight, fast, and flexible library for building web components using standard web technologies such as HTML, CSS, and JavaScript. It weighs in at just 5KB and has a small API surface area, which makes it easy to learn and use. It can be used to build Progressive Web Applications (PWAs) by leveraging its capabilities in building fast, modular, and efficient web components. Its support for web components, reactive data binding, templates, TypeScript, and server-side rendering makes it a great choice for building robust, scalable web applications and PWAs that deliver a great user experience.

Here are some ways Lit can be used in PWA development:

1. Web Components: Lit provides a simple and powerful way to create and use web components. Web components are a key component of PWAs, as they allow for creating reusable and modular UI components that can be used across different application parts. Lit’s lightweight and flexible API makes creating and using web components that work seamlessly across other browsers and devices easy.
2. Shadow DOM: Lit uses the Shadow DOM API to encapsulate web component styles and behavior, creating reusable and encapsulated UI components that can be used across different parts of the application. This allows for improved code organization, maintainability, and reusability.
3. Reactive Data Binding: Lit supports reactive data binding, which allows for the creation of dynamic and responsive UI components. With Lit, you can easily bind data to UI elements and update the UI in response to changes in the data. This is particularly useful for building PWAs that are fast, responsive, and engaging.
4. Server-Side Rendering: Lit can be used with server-side rendering (SSR) frameworks such as Node.js and Express to pre-render web components on the server and serve them to the client. This can improve performance, allowing for faster initial load times and improved SEO.
5. Progressive Enhancement: Lit allows for creating PWAs that progressively enhance functionality based on the user’s device and network conditions. For instance, you can use Lit’s lazy loading and conditional rendering capabilities to load only the necessary parts of your application based on the user’s device and network conditions.
6. Templates: Lit provides a simple and powerful template system that allows you to define your UI components using standard HTML templates. Templates are a key feature of web components, as they will enable you to determine the structure and behavior of your UI components in a declarative and readable way.
7. TypeScript Support: Lit has built-in support for TypeScript, a statically-typed superset of JavaScript. TypeScript provides type-checking, auto-completion, and other advanced features to help you write more reliable and maintainable code. Lit’s TypeScript support makes building robust and scalable web components easy to use with the latest web technologies.

Conclusion

PWAs are undeniably the next step in delivering interactivity and functionality to web applications. PWA technology makes the process of accessing application functions convenient for users.