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name: build-mobile-threejs-games description: Build, tune, or test a Three.js game for mobile web. Use for touch movement, action controls, target selection, touch inventory, safe areas, portrait/landscape layouts, responsive HUD, battery/performance budgets, and real mobile browser QA.

Build Mobile Three.js Games

Treat mobile as a primary control and performance surface.

Controls

Provide a clear movement control, reachable primary actions, target selection, cancel/reset paths, and non-drag alternatives for inventory. Keep controls out of unsafe areas, avoid overlapping action zones, and show feedback for held, unavailable, and queued actions.

Responsive HUD

Design for representative portrait and landscape viewports. Keep vital status, target data, inventory, tooltips, and dialogs legible without covering the playfield. Support orientation changes without resetting gameplay state.

Performance and QA

Use device-appropriate quality defaults and adaptive decorative effects. Test touch targets, multi-touch, long sessions, audio unlock, pause/background return, reduced motion, low-end quality, and actual mobile-size viewports in the repository-approved browser.