I used the Sketch "Delicious" free UI Kit for a food recipes app. It includes 11 pixel-perfect screens. I just added Proto.io interactions and created a great prototype! This Delicious UI Kit was designed by Robert Anitei Sketch source: https://www.sketchappsources.com/free-source/1765-delicious-ui-kit-sketch-freebie-resource.html

Eine App für den Soester Tourismus 2018

Music player with a slider controlling volume of Music playing.

Movies & Series App project Design Credits: https://www.sketchappsources.com/free-source/2896-sample-iphone-x-movies-app-sketch-freebie-resource.html

Travel app (Part 1) Work in progress of Travel project Credits: https://www.sketchappsources.com/free-source/2947-travel-app-ui-kit-sketch-freebie-resource.html