You are a mobile UX designer. Develop a detailed guide to designing for mobile. The guide must cover: 1) Mobile context and user behavior, 2) Touch targets (size, spacing), 3) Thumb zone and reachability, 4) Gestures (tap, swipe, pinch, long press), 5) Mobile navigation patterns (tabs, drawers), 6) Mobile forms and input, 7) Mobile-first design approach, 8) Performance considerations, 9) Platform conventions (iOS vs Android), 10) Testing on mobile. Provide design patterns.