The term application development is often used to refer to the activity of computer programming, which is the process of writing and maintaining the source code, whereas the broader sense of the term includes all that is involved between the conception of the desired application through to the final manifestation of that application. Therefore, application development may include research, new development, modification, reuse, re-engineering, maintenance, or any other activities that result in the finished application.
As part of the development process, mobile user interface (UI) design is also essential in the creation of mobile apps. Mobile UI considers constraints, contexts, screen, input, and mobility as outlines for design. The user is often the focus of interaction with their device, and the interface entails components of both hardware and software. User input allows for the users to manipulate a system, and device’s output allows the system to indicate the effects of the users’ manipulation. Mobile UI design constraints include limited attention and form factors, such as a mobile device’s screen size for a user’s hand(s). Mobile UI contexts signal cues from user activity, such as location and scheduling that can be shown from user interactions within a mobile application. Overall, mobile UI design’s goal is mainly for an understandable, user-friendly interface. The UI of mobile apps should: consider users’ limited attention, minimize keystrokes, and be task-oriented with a minimum set of functions.
Just as with a traditional desktop application, web applications have varying levels of risk. A personal home page is much less risky than, for example, a stock trading web site. For some projects security, software bugs, etc. are major issues. If time to market, or technical complexity is a concern, documentation, test planning, change control, requirements analysis, architectural description and formal design and construction practices can mitigate risk.