Hi Product Hunt 👋 I'm Sungkyun, a solo developer in Seoul, where carom (3-cushion and Korean 4-ball) is what most people play. The problem: at the table you *know* there's a shot, but you can't see it, and nobody's there to show you. Hello Billiard is the friend who leans over and says "thin hit, high right, three rails — about 60%." How it works: • Photo → table. Point your phone at the table. It finds the four cushion corners, corrects the perspective, separates the cue ball from the object balls, and draws the paths back onto your photo. • Physics, not a lookup table. It searches combinations of follow, draw, stun and side spin and shows up to five distinct paths. The success rate is a Monte-Carlo estimate — the same shot replayed 90 times with aiming/speed/tip errors sized to your level (beginner / intermediate / advanced) — so a beginner never gets recommended a shot they can't make. • System numbers on the rails. Five-and-a-half, Plus and Ball systems computed for the current layout and drawn at the actual rail positions, plus which system fits this position at all. • Tune it to your room. Cushion rebound and ball roll are adjustable and remembered, so the paths match *your* table. • Game mode. A difficulty ladder (same difficulty, different layout per player) so you can compete without copying each other's shot — plus handicap match, score race, daily layout and weakness drills. It runs in the browser as a PWA (add to home screen → works offline), and there are iOS and Android apps. Photos are processed on-device and never uploaded. The basics are free; Pro is a one-time purchase, not a subscription. Interface in English and Korean. I'd love to hear from 3-cushion players: which shot types or systems should it handle next?

Hello Billiard

Photo the table, get your carom shot with a success rate

Photo the table, get your carom shot with a success rate