This 18 Cool Gradients was designed by Osama Dawood https://www.sketchappsources.com/free-source/3607-gradients-ui-kit-sketch-freebie-resource.html

Going to a screen depending on a picker selection using states, variables and the 'Fire an items event' action

Showing a random image each time a button is pressed. Project was created using Variables and States

Scrollable Landing Page Design from: https://www.sketchappsources.com/free-source/1975-key-t-one-page-website-template-sketch-freebie-resource.html Top Menu and Side Slider changes (State) depending on the scroll position with the use of variables