I want to bring my “Color-Echo” concept to life on Android. The core loop is deliberately simple: a small grid of coloured cells, one tap per turn, the tapped cell shifts hue and its previous colour floods into the four neighbours. A level is solved when every tile shows the same colour, and an “echo” playback of the move sequence then challenges the player to repeat or streamline it, adding a light memory layer that keeps the puzzle feeling fresh. Visual tone should be cartoonish and vibrant, with lightweight animations that read clearly on all phone sizes. Please pair this with upbeat, cheerful music and crisp, satisfying tap-based sound effects; silence between moves is fine, but every interaction needs audible feedback. Monetisation and quality-of-life features are part of the brief: • First 50 levels unlocked; a single IAP opens the full catalogue. • Rewarded-ad hints. • Optional colour-blind friendly palette toggle in Settings. Deliverables • Production-ready Android build (APK/AAB) plus complete Unity/Godot project files. • At least 150 handcrafted levels grouped by difficulty and a simple editor or generator so I can add more without code changes. • Fully functional echo-preview system, IAP flow, rewarded-ad integration, level-select UI, settings panel, and save/restore of progress. • App icon, store screenshots, and a 15-second gameplay trailer. Acceptance criteria – Smooth 60 fps gameplay on mid-range Android phones. – Palette toggle switches instantly without a reload. – IAP and ad flows meet Google Play policy and pass internal-testing review. – No crashes or memory leaks during a 30-minute automated tap test across two Android OS versions. Clean, well-commented code is essential so I can tweak mechanics or art in future updates. I’ll review milestone builds through Google Play internal testing and provide prompt feedback at each stage.