Have you heard of single page applications (SPAs) but need clarification on what they are or how they can benefit your business? If so, don't worry. This blog post will discuss the critical components of SPAs and explain why having a SPA framework is essential for digital product success. We'll also share advice on creating a SPA that offers customers an unbeatable user experience — regardless of whether it's accessed on mobile or desktop devices. So if you want to gain insight into SPAs and potentially take advantage of their powerful advantages, keep reading!

Table of Contents

What is a single page application?
How do SPAs work?
Single page application vs Multi-page application
The architecture of single page applications
Single page application pros and cons
Single page application frameworks
    ➤  React.JS
    ➤  Vue.JS
    ➤  Angular.JS
    ➤  Next.JS
Single page application examples
Why your business needs a single page application

What is a single page application?

A single page application is a web application that loads only one HTML page and dynamically updates the page as the user interacts with it. Using a single page platform, applications can provide a smoother and more seamless experience for users who don't have to wait for a new page to load after clicking different components. SPAs also require less data transfer between client and server since all resources are loaded only once. It makes single page applications fast and responsive, allowing them to compete with traditional desktop applications in terms of speed. In general, single page applications are becoming increasingly popular among developers due to their relatively easy setup and robust security features.

How do SPAs work?

Understanding single page applications are the key to unlocking a simpler and more efficient development experience. SPAs have revolutionised how we design, create, configure, and use our web applications. Instead of having multiple pages spread across several files, SPAs store all of the code for an application in a single, unified project. This enables developers to update their applications quickly and improves end users' performance since there's no need for endless calls to an API or the server itself.

Single page application vs Multi-page application

When choosing a web application that best suits your business needs, single page applications (SPA) and multi-page applications have their merits.

A multi-page application (MPA) is a website or application designed with HTML, CSS, and JavaScript that uses server-side logic to dynamically generate HTML pages in response to requests from the user. These apps are usually built on top of a content management system. They are typically made up of multiple pages with different URLs, each with elements that must load from the server before the browser can render the page.

On the other hand, SPAs are built using JavaScript and run entirely in the browser without any server-side code being run. SPAs rely heavily on APIs for data retrieval and updating and client-side logic for the dynamic rendering elements within the page. SPAs are typically much faster than multi-page apps due to their ability to render data without reloading entire pages from scratch each time you make a request.

When to use a multi-page app

A multi-page app will likely be sufficient if your application has simple, read-only requirements – such as displaying information but not allowing users to update it.

Additionally, if your application needs to function across browsers that don't support JavaScript or lack modern features like AJAX, then using a SPA might not be feasible. Finally, if your team is unfamiliar with JavaScript or TypeScript development techniques, going with a traditional web app could make more sense, given their familiarity with HTML and CSS frameworks.

When to use a single page app

Suppose your application requires rich client-side functionality that doesn't need reloading the page every time something changes. In that case, a SPA will likely provide better performance than its non-JavaScript counterpart would offer.

Additionally, suppose your application needs functionality beyond what typical HTML forms offer. Then, a SPA could provide you with those features without having to write complex server-side code for those functions themselves. L

Lastly, if you have existing APIs available that can handle most of the logic required by your application, then leveraging those APIs instead of reproducing that logic in server-side forms might be simpler in many cases too.

In the end, you'll need to decide which features are most important for your application before deciding between single and multi-page technologies.

MPA vs SPA lifecycle.
MPA vs SPA lifecycle


The architecture of single page applications

The browser receives an HTML file from the server when you request a web page. With a SPA, the server only delivers an HTML file on the initial request; future queries receive JSON data.

According to the rationale above, a single page application will rewrite the content on the current page rather than the initial page load. As previously stated, this results in no page reloads and no additional waiting time.

With dynamic content loading, single-page web applications feel like native desktop or mobile applications, providing a natural user experience.

Single page application pros and cons

Sites using single page applications are more efficient in processing, cost less than standard multi-page sites, and need less work from developers because they can employ repeating layouts and operate as "content on demand" apps. But while there are many advantages to single page applications, it is essential to consider the tradeoffs when discussing the pros and cons.

The pros of SPAs

1. Faster loading speeds

MPAs send server requests all the time, which are subsequently processed as database queries. The database answers, the server executes the query, and finally shows the pages. That's a lot of patty-caking, which slows page load times.

Meanwhile, SPA sites download everything at once, eliminating back and forth; new information is loaded as a single page rather than as a process that needs to request more HTML pages inside the site design. JSON allows for increased speed and efficiency, resulting in rapid access to all features and operations of the site with no wait.

Also, because of caching (more on that below) and reduced data quantities, navigating between sites using a SPA is sometimes faster. Only the necessary data is sent back and forth. The application will only download the missing pieces even if a user requires the submitted data. As a result, the entire operation is faster than with MPAs that load pages with each request.

2. Capabilities for caching

SPAs only request data from the server once. If a user has a poor internet connection, site data can be retrieved with the server when the connection improves.

Additionally, the browser will periodically check to see if the cached data has changed, even if the SPA is a landing page and only downloads the data once. When anything changes, an application asynchronously retrieves it.

3. Improved user experience

Single-page applications also offer a superior user experience. Users of an MPA must navigate through links and menus to find the information they seek, whereas users of a SPA only need to scroll. Because of this property, SPAs are particularly well-suited to mobile situations.

Furthermore, a SPA allows users to access a website even if their internet connection is terrible, and it is often easier to engage with a SPA from any device. The experience is ongoing without needing a page refresh, and navigation is faster overall since it reuses page elements.

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The cons of SPAs

1. Slow in some cases

Because the JS volume in SPAs is substantially larger, initial loading takes longer. Furthermore, because it needs to analyse and interpret the JavaScript data, a mobile browser can drastically slow down app loading - especially if the smartphone's processor isn't powerful.

2. Issues with search engine optimisation

Having a single page rather than numerous pages can harm your SEO since search engine crawlers must deal with JavaScript rather than HTML (the format with which they are better comfortable). Only Googlebot (Google's web crawling machine) can render JS pages (rather than Bing or Yahoo! ), but you could still get good rendering with SPA; it's just a little trickier.

Server-side rendering, pre-rendering, and feature detection can all be used to reduce SEO friction.

3. Website statistics

Another issue is that SPAs impact the accuracy and usefulness of website traffic measurements. Because you have one page to compare it to, it can be challenging to determine which sites or content are the most popular with SPAs. Google Analytics, for example, collects information on each page downloaded from a website.

To track the activity on a SPA, you must manually configure the default Google Analytics tag to track page views on a SPA.

4. There is no way back

Finally, internet users frequently press the "back" button when perusing a webpage. Going back to a single page application removes them entirely from the app or site, which is inconvenient and even a deal-breaker for users.

If you're ready to develop a complicated SPA, there are workarounds, and it's even possible to build a landing page SPA where "back" works. However, some believe that this contradicts one of the fundamental goals of SPAs: simplicity.

Single page application frameworks

It's essential to create a SPA on a solid foundation. The top single-page application frameworks that can handle the expansive application architectures needed for rich web apps have unique attributes and capabilities. The best SPA framework, however, will depend on your company's needs.


Scalability and flexibility, previously an afterthought, are now critical emphasis areas for organisations in today's dynamic digitised environment.

Thus, designing an efficient single-page application requires this essential element. ReactJS is a good framework for businesses that prioritise scalability and flexibility.

  • ReactJS is the finest framework for SPA development since its stand-alone libraries make it flexible and fast.
  • ReactJS pages have Virtual DOMs. It allows the development team to track and update changes without affecting other portions of the tree, improving application flexibility.
  • React's component-based architecture makes single-page application maintenance easier.

Since both client and server use ReactJS, the framework distributes the load.


VueJS is the greatest single page web application framework with the proper libraries and modern tooling.

Vue.js' minimal size is a significant benefit (18-21kb). It's easy to download and use for further benefits:

  • Vue.js is neither library nor a framework. It contains the ideal mix of functionality for constructing SPAs, and adding State Management and Routing is trivial.Vue.js's MVVM architecture makes handling HTML blocks straightforward for two-way communication.
  • Vue.js is the finest of React and Angular. It leverages Virtual DOM and components like React, making it quick. However, directives and two-way data binding make it reactive, like Angular.
  • Vue.js is neither library nor a framework. It contains the ideal mix of functionality for constructing SPAs and adding State Management and Routing is trivial.

Read more about Vue.js vs React.


Enterprises struggle with application "Performance" while pushing the web to accomplish more. More than ever, webpages contain distinct characteristics, making it difficult to run well across devices.

Performance difficulties can cause slight delays or make your SPA unresponsive, driving customers away. Thus, selecting a single-page application framework should prioritise performance. AngularJS is the best framework for single-page app performance.

  • AngularJS data binding reduces developer code. Thus, Angular's single-page applications are fast and need less code.
  • Fast-loading AngularJS apps. AngularJS's component router automatically splits codes. Users can load only view requester code.
  • AngularJS makes SPAs cross-platform.

Read more about Angular vs React: a comparison of both frameworks.


Instead of using the user's browser, NextJS's server renders each page. After a request, the user obtains a fully displayed page faster.
Next.JS employs Server Side Rendering (SSR) or Static Site Generation (SSG) to generate HTML on each server request or during compilation.
So, it renders pages at request or creation by using SSR and SSG interchangeably. This flexibility improves website loading and data fetching.

  • Due to the SSR used by Next.js, a given application's information can be instantly available for SEO. since the page has HTML delivered by server-side rendering.
  • Next.JS renders on both the server and client, making it isomorphic. This reduces the loading time for the end user and eliminates the need for client-side JavaScript to render the page on the first load.
  • Next.js renders an app's content on the server, so slow devices can load it quickly without affecting the user experience.

Read more about what's new in Next.js 13 - features, improvements, and more.

ASP.NET (Blazor)

For single-page applications, we added ASP.NET. Blazor is new and, according to the GitHub repository, describes it as a.NET framework that uses C#/Razor and HTML to run in the browser with WebAssembly.

Blazor allows C# logic without TypeScript or JavaScript, making it convenient. Blazor supports JavaScript APIs and libraries, so you won't be lost in the move if your ecosystem is vast and uses JS libraries.

.NET Blazor also offers two different options – client-only Blazor and server-side Blazor.

Does it mean that Blazor will kill Angular, React, or Vue? We disagree. However, it is something to keep an eye on.

Single page application examples

The sites ideal for SPAs is those with dynamic nature, frequent updates, and large amounts of data that need to be accessed quickly by users.

Some examples include:


Gmail is a single-page application; thus, clicking messages in your inbox doesn't need you to reload the page. This happens because all the data is loaded from the server at once. The same goes for Google Calendar, Drive, and Google Maps.


It’s an online writing aid that evaluates your grammar and spelling in real time due to AI, extensive SAP capabilities, and a Vue.js framework. As a result, users can obtain Grammarly real-time advice straight from Google Docs to make their writing clear, precise, and intelligible.


An online entertainment and streaming platform Netflix is built on the React framework, so delays do not interfere with the user's viewing experience. Netflix can broadcast massive amounts of data to multiple platform users using a SPA technique. Netflix loads new data only in the browser when a viewer makes a new request, which accounts for its quickness.

Why your business needs a single page application

As business owners look for more efficient and cost-effective ways of meeting their customers' needs, many are turning to single page applications as the go-to solution. Not only do single page applications eliminate the need to wait for pages to reload, saving time for consumers, but developers also benefit from faster development cycles and improved code maintainability. As a result, businesses can reduce costs associated with maintenance and deployment while at the same time enhancing customer satisfaction levels.

By reducing complexity in front and backend systems through a unified model of execution, a single page application allows businesses to deliver smoother and more responsive customer experiences. Thus, companies should consider using this technology as they look for innovative ways to serve their customer base better.


SPAs offer a range of advantages over traditional multi-page web applications. They are faster, more responsive and provide a smoother user experience which is why every business should consider developing a SPA. If you're unsure where to start, our team of experts at Imaginary Cloud can help you plan and build your very own SPA customised for your business needs.

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