Seval widgets handle touch events for you on mobile devices
Layoutallows you to assigned GUI elements size by inch rather than pixel,so their sizes will be all the same on screens with various sizes&resolutions
SetupJust attach the one root script to a GameObject then create&edite elements in Inspector View
TestA preview of the target screen will be displayed in th Scene View if you assign a combination of screen size&resolution. no need to run at all
Touch eventRegist a method of a script and the GameObject that script attached to, messages will be send when a GUI element is touched