Don't rush into programming ! If you need a simple tool to prototype the design of your mobile apps before programming, NinjaMock ( http://ninjamock.com ) is a nice tool to quickly create a wireframe containing the interaction logic of a user interface and get a simple representation of the look of the pages you want to build for your app. FluidUI ( https://www.fluidui.com ) does the same job already but is mainly featured for Android and IOS and free version is very limited (one project only). NinjaMock allows to build prototype for many platforms (Android, IOS, Windows Phone, Windows 8 or Web) and it's free. Be creative ! ;)