Who's at the Door?
Who's Knocking? Open Up!
Get picks like this daily. Today's launch numbers, the top launches, AI and tech news, and a daily opportunity pick, straight to your inbox.
Read the full description
Knock knock. Who's there? Better check… then CLOSE IT. DuoDoor is a door-closing reaction game built around the hinge of iPhone Duo. Your phone is the door. Unfold it to peek inside, and if something nasty lunges at you, fold it shut as quickly as you can. Your reflexes are timed to the millisecond. KNOCK. PEEK. FLINCH. Listen. Someone is knocking from inside, and you'll hear and feel every knock. Unfold your iPhone Duo to slowly open the door. A burglar? A raccoon with your keys?
Visit website ↗ Source listing ↗
PH · launched Oct 28, 2026 · 5 upvotes (top 6%)
- Security
- B2C
- Commercial product
- iOS
- Games
Similar launches
See all 290 similar launches →Could you build this?
Partial The door-closing reaction game itself is simple to build, but its core mechanic depends on reading foldable-hinge angle from a specific device, which is platform- and hardware-dependent.
What it would actually take: The game needs a real-time hinge-angle signal, which must come from the device's sensors or an OS API that exposes fold state. Without that access, a builder would have to approximate the mechanic with a gyroscope or accelerometer, which changes the gameplay. Building a faithful version requires platform-specific native development and access to hardware-level sensor data.
Competitors
Other products that read as similar to this one : 290 launches clear the similarity bar, closest 8 shown.
Attention rank: #19 of 291 (itself plus its competitors, highest first, normalized so YC and Product Hunt are compared fairly).
Launched 343 days after the earliest competitor.
- Fold Toys: Spooky iPhone Duo App · ph · 2026-10-27 · 1 upvotes · similarity 0.62
- Orisuji, a maze you solve by folding your phone · hn · 2026-10-24 · 11 upvotes · similarity 0.49
- Peeked · ph · 2026-10-27 · 3 upvotes · similarity 0.49
- Knock · ph · 2026-10-26 · 73 upvotes · similarity 0.48
- Indistractable · ph · 2026-09-15 · 3 upvotes · similarity 0.47
- duo-open · github · 2026-09-11 · 35 upvotes · similarity 0.46
- Duo · ph · 2026-09-18 · 1 upvotes · similarity 0.46
- Stress Less - Built for iPhone Duo · ph · 2026-10-24 · 3 upvotes · similarity 0.46
Other launches for this product
- No other launches for this product.