Fitts’ Law states that the time to acquire a target is a function of distance and size, but its assumptions don’t always apply to touch interfaces. Targets are not always closest to the user’s hands, which are often obscured. Guidelines like bigger targets being easier don’t translate when hands are held in many positions. Designs also tend to assume focused attention, but mobile users live in the real world with distractions. Context considerations are important, like controls fading too fast.
It provides an updated checklist for touch best practices, focusing on discoverability, distraction, and guarding against accidental actions. Overall, this was a thoughtful re-examination of a foundational law for designing intuitive interfaces in today’s multi-modal, mobile-first world.
