Be it an iOS, Android, or Windows platform you want to build a mobile app for, your app should "feel at home." It’s important to determine the functionalities and features to be added in the app.
Sketching a visual map of new mobile UI is a good start. This will be useful to validate product concepts and design approaches. Our teams use Pencil tool to create such visual guide that represents the page structure, as well as its hierarchy and key elements. This is very useful to discuss ideas with team members and clients, and to assist the work of designers and developers.
Then comes the prototyping, which is a simulation of the navigation and features, commonly using clickable wireframes or layouts. It's a quick way to test and validate a product before fully developing it. We leverage Photoshop CC to create such prototypes.