1. A method comprising: detecting, by a user device, an area of a touch screen that is touched by an instrument; determining, by a user device, a gesture corresponding to the area touched; performing, by the user device, a crossover operation when it is determined that the gesture corresponds to a crossover gesture; and displaying on the touch screen, by the user device, a content that includes a first child content and a second child content, that is associated with the crossover operation, where the crossover operation includes navigating between the first child content to the second child content in response to the crossover gesture, where the first child content is accessible via a first parent content and the second child content is accessible via a second parent content, and when navigating between the first child content to the second child content, the first parent content and the second parent content is not displayed.