How is Single Page Application different from Multiple Page Application?

Until a couple of years back, when you clicked a link or typed a URL, you had to wait a few seconds for the page to be loaded. Lately, some web-pages seem to react instantaneously to our clicks and commands. Also, there are others that continue to work the old-fashioned way – a reload indicator going on and on as you wait, indicating that the page is being loaded.

This difference in speed is essentially what Single Page Application and Multiple Page Application is all about. In our earlier blog, we had discussed building a Single Page application using AngularJS. We shall now discuss how Single Page application differs from Multiple Page Application.

A Single Page Application or SPA loads a single page and dynamically updates portions of that same page, every time the user clicks some link or interacts on that page. Some popular Single Page Applications are Gmail, Google Maps, Facebook, Twitter, Flickr, etc.

A Multiple Page Application or MPA fetches an entirely new page from the server each time you click a link. This is the reason for the delay while using web pages operating on MPAs.

Let’s delve a little deeper into the differences between these two technologies and their pros and cons.

Behavior:

SPA displays a highly reactive behavior. Since they allow development of a feature-rich application, the user experience is similar to using a mobile or a desktop application. Quite opposed to this, MPAs have an entirely new page fetched from the server every time a link is clicked – therefore slightly delayed.

Browser support:

SPA tends to support more modern browsers and not the traditional ones. While they do work on both, traditional browsers lack a lot more tools and options. If the application requires working on the vast majority of browsers, then MPAs might be preferred.

Search Engine Optimization (SEO):

SEO can be challenging while working with the SPA. While there are tools available, they are still in their primitive stage. The developer needs to have in-depth knowledge to bridge the gap. In the case of Multiple Page Application (MPA), the SEO system sees what the user sees. It fetches its data from each page that is being downloaded from the server. Hence SEO is effective. In the SPA, there is no downloading of a fresh page, but only parts of the page are re-rendered. Hence SEO may not be effective unless designed appropriately.

Caching:

In case of SPA, all the data is stored locally once the first request has been made and fetched from the server. Subsequently, even if the app goes offline, the SPA can be operated. In an MPA once the devices lose connectivity nothing is available locally.

Application development:

While speed and the visual experience of the site are all that matters for a user on the internet, there may be much more to it for an application developer.

Ease of application development:

From a developer’s perspective, using a SPA may be complicated for creating feature-rich applications. In the case of MPA, as a separate page loads for each link, structuring the project might have a clear approach. Majority of web pages are MPAs, hence lots of best practices and tutorials are available on working with MPAs. Due to this, it may be the preferred choice of novice developers.

Application development period:

In SPA, the front-end developers and back-end developers can work independently of each other. They do not interfere. Hence development can be completed quicker than MPA, as they can work in parallel. This is not possible with MPA as the classical project design is rigid and requires both backend and frontend to work in tandem.

Security:

Due to cross-site scripting, SPAs are more likely to be less secure. MPA, on the other hand, is known to better security and integrity of data.

Platforms used:

Both SPA and MPA are written using JavaScript. However, there are fundamental differences.

SPA uses more powerful technologies like React.js, AngularJS, Vue.js EmberJS, etc. This allows flexible and stylish applications on the front. They depend on JavaScript frameworks to do the cumbersome job of managing the data.

MPAs, on the other hand, have a classical architecture. These are mostly developed using JavaScript /jQuery. Since this is now a legacy technology, there are lots of best practices and tutorials available that can help in developing secure websites. For example, Magento, OpenCart for e-commerce; Dolphin, Elgg for developing social networks and so on.

Cost difference and Ease of implementation

SPA is relatively new to the market, and the cost of development might seem to be on the higher side compared to the MPA. Also, it may be a challenge to find new developers with knowledge of new technologies. Debugging may be difficult as a lot of tutorials or libraries may not be available as compared to MPA. These may shoot up the costs for SPA.

However, in the long run, especially where there is a long-term product vision, the SPA seems to be the choice of posterity.

The bandwidth consumed is reduced in SPA which means reduced data consumption and lesser charges.

There is flexibility to develop different front ends for different consumers using the same back end. This once again has a positive impact on cost.

There is no need to write codes for loading each page separately as in the case of MPA. As a result, it reduces the time and cost of development and is faster to implement.

Like with any new technology in the market, SPA too is getting upgraded each day with newer features to combat those few shortcomings.

User friendliness

User experience in MPA is poorer as compared to the SPA. Tighter link and communication with the back-end server is the primary reason for this kind of experience. In a Single Page Application, the user never has to wait, and the experience is similar to using a mobile or a desktop app. This is a considerable advantage and a significant reason why SPAs are so popular these days.

SPA or MPA for your business?

SPA is the in thing – undoubtedly. However, it has its flip side. Therefore, it may be wise to consider the requirements and priorities of the application being developed while making a choice between SPA and MPA.

For instance, if the concerned application has a social media function – SPAs can give that ultimate comfort and speed. Twitter, Facebook, Gmail, are all SPAs. Alternatively, if the application demands access to a large pool of data, is highly content oriented, and requires SEO then MPA would be the right choice. In this case, the end-user experience has to be slightly compromised.

In conclusion, answers to a few questions could help in choosing between SPA and MPA. Does the application demand best-in-class user experience? Is SEO a core focus of your application? What is the security level of the data that is being handled by the application? Is there a scope for future scalability of the application?