How do you optimize e-commerce for mobile shoppers?

Mobile optimisation is critical - 65%+ of e-commerce traffic is mobile. Optimisations include: mobile-first design (designed for phones, scales up for desktop), thumb-friendly interface (buttons easily tapped), fast loading (under 3 seconds on 4G), streamlined navigation (hamburger menu, clear categories), large product images (pinch to zoom), simplified filters (most important filters prominent), one-tap checkout (Apple Pay, Google Pay), autofill forms (address autocomplete), and persistent cart (cart follows across devices). Mobile shoppers behave differently: shorter attention spans, thumb scrolling, portrait orientation, variable connectivity. We optimize images aggressively (smaller file sizes), minimize text (concise descriptions), prioritize features (above fold content), and implement progressive web app features (feels app-like). Mobile conversion rates typically lag desktop by 50%, but proper optimisation closes this gap. Testing on actual devices ensures quality - what works on desktop simulator doesn't always work on real phones.