Mobile apps · Beginner

Mobile UX: what's different from a large screen

In one line: On mobile the user is standing, rushed, holding with one hand and sometimes in sunlight — and that changes every decision.

Touch areas and order

The top of the screen is hard to reach with a thumb. Primary actions belong at the bottom. A comfortable touch area is about a finger wide — smaller buttons produce mis-taps that register on your side as “confused users.”

Reduce typing in every way: selecting from a list, scanning, autofill, location detection.

Interrupt less

Permission requests, ratings, and popups on launch are where apps lose people. Time them after success, not before the start.

Edge states that really happen

An incoming call mid-process, a locked screen, switching between networks, low battery, and power-saving mode. The app should return to the exact place with what was typed. Losing a form after a phone call is a very common and unforgivable bug.

Going deeper

Test the screens in direct sunlight and in dark mode, and at an enlarged text size set through the system. All three break layouts that looked great in the lab, and they're far more common than you'd think.

Users