Applications, or more commonly known as apps, are indispensable in our current society. For example, more and more processes are being automated by replacing people with technology. For example, there are apps that provide information about the daily weather or traffic situations as well as apps that make everyday life easier such as internet banking, and paid parking. In addition, we use apps for education and relaxation purposes, including language courses, and recreational and professional games.
Thus, apps can be differentiated by their purpose: Informative, Educational, Practical, Relaxation.
All those apps can be downloaded from the Apple App Store or the Google Play Store, which are connected to the two largest mobile operating systems, iOS and Android. Obviously, there are more, like Microsoft, but considered less important. The different stores require different operating systems, so an app is often developed in several frameworks and programming languages. This makes them readily available for use in iOS, Android and Microsoft.
Because each operating system is different, a Software Development Kit (SDK) is readily available for all options. These kits are the basis for the development of an app, and are accessible to all. With a background in IT, developing an app is rather simple, for more complicated (design) requirements it is advisable to hire a professional developer.
Most apps are updated on a regular basis, which may be due to security reasons or to make usability improvements. Therefore, an app has a specific version number listed in their respective stores.
