Business Software, Web Applications and Desktop Software Compared

It has been some time that an argument has been doing rounds about the replacement of desktop application by web applications in the business software category. Although, web applications are more versatile and flexible, desktop software and applications are not easily replaced considering the issues of security and replacement of legacy systems that have been in place for some time now. The shift if it ever happens is not only a technical issue but also a marketing and business issue. A lot of information is available on a website that discusses these issues under various heads and articles.
A desktop application is localized on computer or a local area network where it is deployed whereas a web application is delivered to users across the globe using a web server connecting through the internet. Usage of a web browser as a client is finding more and more acceptance today and is being used in many applications and off the shelf products to deliver better GUI's. This has led to the popularity of web applications. It is very important to understand the delivery systems on the internet to find suitability of converting a desktop application into a web application. Applications integrating search engine optimization techniques have become more popular in businesses that are marketing or sales oriented, while a manufacturing unit may find it less appealing to convert the existing application into a web application.
A few points come to light in comparing a desktop application and a web application.
Accessibility: A desktop application is accessible only on a local computer, whereas a web application is available anywhere across the globe.
Maintenance & Upgrades: Web application need less or no maintenance since they are installed only once on the web server, whereas desktop applications need to be deployed individually on each computer. Upgrades and other compatibility issues are mostly taken care of by the webmasters of the hosting company unlike desktop applications. The maintenance of a web application is of prime importance, since the business puts all its eggs into a single basket, uptime is not only necessary but crucial to the application.

Security: Working online has its own set of risks like hacking and virus threats. The risk is higher compared to a desktop computer, since a malfunction of the desktop can result in loss of partial data. The crash of a web server can result in consequences beyond the control of a business.
Cost: Running a web application involves recurring cost of web space and bandwidth use, whereas, the use of desktop has a one time cost and has been known to cheaper over a period of time.
Connectivity: The reliability of web applications is based on connectivity, although they can be used from anywhere across the world, connectivity speeds and bandwidth regulation may render it useless in some areas. Failure of internet connection from the business end or the web server end can cause unwarranted delays. Critical applications may suffer as a result of these interruptions in service.
Slower: Web application in comparison to desktop application run slower due to transfer of data through the internet. The speed of connectivity and bandwidth usage may be major factors.

The popularity of web applications is only due to the accessibility despite their limited functionality.