Lecture 7 of Stanford’s CS193p iOS Development course from Spring of 2021 begins with an explanation of ViewModifier, including a demonstration of how to create a custom Cardify ViewModifier for the Memorize game. The lecture then transitions into an in-depth look at animation, covering topics such as implicit vs. explicit animations, Animation structs, transitions, matched geometry effects, the impact of container views, Shape animations, animating ViewModifiers and more. We begin the first part of a two-lecture-long demo by illustrating how to use implicit animation to spin an emoji when a card is successfully matched in our Memorize game. Throughout this process, we constantly refer back to some golden rules of animation, and demonstrate how to use them to diagnose problems when our animations fail to behave as we expect.