The first factor that influences the utility of any app is its compatibility with the SE. If the technology used for the app design and development are not SE compatible, it can lead to impediments in its downloading. The images and other visuals may not be visible to the visitor. This means that the app cannot convey the message that it has to convey to the visitor. In this case the purpose of the existence of app is not served. Any professional app designer has to keep this issue of compatibility into consideration when designing and developing any app.
The other element of importance is the content and the language used. They should be such that the visitor finds it interesting in reading and navigating through the app. It should be like the pitching of a sales representative especially at being persuasiveness and assurance of the service being reliable. The buyer will buy the offerings of the app only after being assured of its quality and it being worth the price quoted.