Why the time has come for browser applications

Since web applications first appeared, the standard method of presenting the user interface has been for each the server to generate a new page of HTML in response to each request from the browser, so that the browsercompletely redisplays the page after each request.  This leads to a "clunky" look and feel, with the continual redrawing of the screen interrupting the user's natural work flow.  During 2005, the buzzword AJAX appeared, referring to a collection of techniques for a web page in the browser to retrieve data in the background and update itself in place, rather than causing a complete page reload.  Most of these techniques had been available for several years, but most developers either did not know about them or thought they were too difficult to use.

AJAX techniques are usually used at the moment to add small clever features to fairly standard web pages.  But it is time to completely rethink the way web applications work, and move to the idea of a fully fledged client application in the browser, written in JavaScript.  This browser application makes HTTP requests to the server application, which contains all the business logic.  The server responds to the browser with only the data resulting from the request, rather than a full web page.  The browser application is responsible for displaying the data as appropriate, using DHTML to create new elements in the page - it does not reload the page.  The browser application creates its own windows within the page by dynamically creating and positioning HTML elements.

Advantages of browser applications

Browser applications bring advantages for both the provider and the users

• Better look and feel
  It is now possible to create browser applications that look very similar to desktop applications, and that can be as responsive, if the server and network are fast enough
• Simplicity of development
  Using a browser application enforces a very clean split between the business logic on the server and the presentation layer in the browser
• Reduced server traffic
  The browser application can do some work itself, such as displaying forms for data entry, that would require a server request in a standard web application.  When it does make a server request, only the data is returned, which could be only 10% of the size of a full HTML page containing the same data
• Reduced server processing
  Generating HTML can be quite heavy processing, especially if techniques such as XSLT are used.  With a browser application, that work is spread out around the client computers.

Other changes

Various other changes are happening at the moment that make browser applications more attractive

• Cross-browser capabilities
  The large differences in the DHTML capabilities of browsers have now largely disappeared, making it much easier to develop applications that will work for nearly all users
• Broadband access
  The JavaScript files containing the application have to be downloaded when the page is first accessed, and they can be quite large.  This would have caused an unacceptable delay on a standard modem, but with broadband access now being widespread, most users would be able to download a typical application in under 10 seconds
• Hosted applications
  More and more applications are being delivered over the web, instead of being installed locally on the customer's own computers.  Browser applications will allow these systems to match the usability of a local desktop application.