Obtuse: Degrees of Chaos

How good is your feel for an angle? Obtuse turns one shared iPhone into a friendly contest of instinct. Everyone gets the same target each round. Tap Start once per round. Each player matches the angle by feel, taps Done, and passes the phone. The target stays visible; your measured angle stays hidden during every scored turn. Pass the phone and keep your poker face—the leaderboard waits until everyone finishes. LEARN BY FEEL Open How to Play from Home or onboarding to explore your real live angle. The number appears only in the lesson; scored turns keep it hidden. No simulated readings. TILT ON IPHONE Tip the whole phone: screen face-up is 0°, upright is 90°, and face-down is 180°. Hold steady for a beat before tapping Done. Tilt uses real device-motion gravity readings and rejects missing, stale or moving input. FOLD ON IPHONE DUO Duo automatically uses Fold on iOS 27.1 or later; ordinary iPhones automatically use Tilt. Gently match the device-reported hinge angle. Stay within its comfortable range. Ordinary iPhones use Tilt—never bend an ordinary phone. A PARTY IN YOUR POCKET • 2–8 players with their own colorful animated faces • One shared target per round, between 35° and 145° • Every round's points, submitted angle and error in a detailed scorecard • Lowest average angle error wins; ties share a place • Solo practice with separate local bests for Tilt and Fold • Reduced Motion support and accessible controls • Offline play, no accounts, ads or analytics Purchase once. No subscriptions. No in-app purchases. Requires iOS 26 or later and device-motion hardware. Fold additionally requires iPhone Duo with iOS 27.1 or later. Scores use device-reported readings, not calibrated measurement accuracy. Keep a secure grip while playing.