In the pre-app era the word "application" had been applied to websites that provided advanced user interactions and capabilities previously available through native software. Examples of search apps are Webmail, Google maps, Google Docs, news sites etc...
In the era where the demand of mobile telephony is on the ascendancy, be it a smart phone or a tablet, there has been an increase in the number of mobile applications on the market in every platform and domain. But the power of the web cannot not be underestimated.
Mobile device sales rose in 2011, with smartphones showing the strongest growth. Nokia remains the number one handset manufacturer, but Samsung is the leading smartphone hardware vendor with android being the top smartphone operating system. Android now powers more than 250 million devices, with a user base increasing by 700,000 subscribers per day. This goes to show the increase in mobile users globally.
Each of these types of apps has their own pros and cons. Here is a summary...
Working offline. A mobile app is best if your app must work when there is no internet connectivity. Though HTML 5 supports caching, it is still limited comparatively.
Speed. Native apps win the speed race. The speed of web apps depends on a persons internet connectivity.
Maintenance. Maintaining a native mobile app can be complicated both for users and developers (dealing with multiple versions of the same information on different platforms). New versions of mobile apps will have to be packaged and placed in the app store. On the hand, maintaining a web app is simple as maintaining a web page and changes can be done frequently as needed.
Platform independence. While different browsers may support different versions of HTML 5, if platform independence is important, you definitely have a better chance of achieving it with web apps than with mobile apps.
Installation. Installing web app is a hassle for users: They need to be really motivated to justify the effort. “Installing” a web app involves creating a bookmark on the home screen; this process, while arguably simpler than downloading a new app from an app store, is less familiar to users, as people don’t use bookmarks that much on mobile.
In a nutshell mobile apps and web apps are all ways to cater for the mobile user. There is no unique best solution, each has its strength and weakness. The choice remains with what you want to achieve, target group and the developers preference.