There’s little consideration about how it all fits together outside of a static comp. You tap a button and the form just …appears? You swipe to delete an item and it just vanishes? That’s super weird and un-natural. Nearly nothing in the real world does anything as jarringly as just swapping states. It would feel like a glitch.
Great piece by Pasquale on an oft overlooked aspect of UI design. Our UX team recently acquired a Nexus 7, Microsoft Surface, and Kindle Fire HD for testing, and what’s the most jarring is the lack of detail to the physics of the interfaces. On iOS, even the interface beyond the canvas is taken into consideration, how you can drag the bottom of a page up and you see the blank area.
These minute touches are what take an interface from feeling functional to completely obvious and natural.