There is always a temptation to consider the problems of Internet connection as something temporary, no matter through mobile data transmission, or in any other way. The problem will solve itself at the moment when the coverage area expands or the connection speed becomes faster, otherwise users can kill time by playing a running dinosaur game in Chrome.
This approach really works as long as your users are above ground in large and well-developed, but not too densely populated cities. However, what happens when users of your application go down the subway, board a plane, take a long journey overland, or move to the countryside? Or when they find themselves in the “dead” corner of the room, or become part of a huge crowd? Your carefully designed application interface becomes a source of disappointment, because it depends too much on an elusive connection to the server.
Such dependence on the network is caused by the neglection of common truth: the lack of a network connection is a harsh reality. At some point, if you move in space, the network connection will disappear. Though, there is nothing to worry about. There are ways to solve this problem - the Offline first approach in particular.
Offline first, you say?
Historically, most of the work on a web page has been carried by the server. Data was stored in the database, accessed through a thick layer of code in a server language like PHP or Ruby, data was processed and rendered in HTML using templates. At the same time, storage, processing and display of information required constant communication with the server.
The offline first approach offloads interaction with the server side. For example, one way to implement this approach is to move the entire MVC stack (Model-Viewer-Controller) to the client side. On the server side, in this case, there is only a lightweight API for accessing the database. This makes server code much smaller, simpler, and easier to test.
The ability to work in offline mode is the best suited for web applications. Imagine an online note-taking web application. A user can write only half a note before the connection of his mobile phone to the Internet is broken. Thanks to stand-alone HTML5 web applications, users who are faced with this situation will be able to continue to write their notes, and data can be sent later as soon as the Internet connection is restored.
A great feature of stand-alone HTML5 web applications is that they are easy to configure and use. The most common way of implementation is to create an autonomous version of the site, but at the time of writing this article, implementation through Service workers technology is the most relevant.
In general, many attempts were made to create technologies that would solve the problem of lack of connectivity, some of the issues were resolved. But still, the most important problem is the lack of a good mechanism for managing the resource cache and custom network requests.
A previous attempt was an AppCache technology, which seemed like a good idea, because it made it really easy to specify resources for caching. However, this technology makes a lot of assumptions about what you are trying to do, and then breaks down with a crash when your application runs contrary to these assumptions.
So what are the advantages of offline mode?
Generally speaking, the offline mode has so many advantages that it will take a huge amount of time to transfer them, and many of them are pretty obvious. Though, we have reduced everything to the three key advantages that stand out the most in web applications with offline mode.
Without an Internet connection, the user can view information and even submit HTML forms. At the same time, the data that the site visitor has entered into the form is temporarily stored on the device, and as soon as a connection to the Internet appears, they will be sent to the server. Imagine, for example, that you started filling out an order form and then went into the subway and the connection was interrupted. On a regular site, if you then click the submit button, your data will disappear; an application with offline mode will save all the information and send it as soon as possible without your participation. This is great news for companies that have product catalogs because it allows their customers to browse products, even if they are not connected to the Internet, which increases user engagement and potentially leads to increased revenue. At the same time, if there are a lot of names in the directory, then it will not be possible to save them all on the client side because of memory saving reasons, this must be taken into account during offline mode web application development. This is most relevant for PWA, but we will talk about them later.
> Improved performance
This is rather a consequence of the above points: when working with web applications equipped with offline mode, the likelihood of a client re-accessing the resource increases, the time he spends on the resource improves the user experience, which in the long run helps increase conversion if it comes to commercial web application.
So, what does PWA have to do with it?
At the time of writing this article, PWA (Progressive web applications) is the main direction for developing offline mode in web applications. Progressive web applications have already gained really wide fame and recognition by all involved parties: browser developers, software developers and users. The idea of applications that are independent from network connectivity has proven its viability, and we see more and more projects moving along this path, which makes the ability to work in offline mode not only best practice, but simply and a good manner on the web. PWA development is no different from creating a regular site. There is no need to create additional APIs - when developing PWA, since the same code is used.
You can read more about them in our article How Can Progressive Web Application Development Improve Your Business. As part of this material, we only note that if your plans are ambitious and you want to implement a progressive web application in an online store or on a corporate website, the best option would be to contact professional developers of IT tools.
You will definitely benefit from this, as in this case the software company provides qualifications, experience and responsibility.
So, we hope we were able to convince you that offline mode in a web application is a really cool idea that provide you with a competitive advantage. But just offline mode is not enough. Firstly, a lot depends on software developers qualification. Secondly, there are many other nuances that must be taken into account. Read more about them in our article How to Make a Successful Web App in 2020.