I was interested to see how animations are executed for Apple Watch apps. These videos shed some light on it: WWDC 2015 Apple Developer Videos. I watched:
- Layout and animation techniques for WatchKit
- Designing with Animation
It seems that a lot of the animations are ‘tricks’ achieved by tweaking the layout groups (either changing size, alignment or visibility). Other recommendations include writing skeleton apps to mock animations by switching between images put together in KeyNote – this enables choosing between competing ideas without taking the time to code them all individually.