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Built for Duo

Knock Knock Simulator

Meet illustrated visitors and finish knock-knock jokes by opening a cartoon front door.

Justin McCahill · Entertainment · $1.99

View on the App StoreSave

iPhone screenshots

Knock Knock Simulator — iPhone screenshots 1
Knock Knock Simulator — iPhone screenshots 2

How it uses iPhone Duo

When closed, the cover shows the inside of the door and lets you knock or peek. Open the Duo to reveal the visitor and punchline.

What’s New

Version 1.8 ·

A clearer App Store page and small under-the-hood improvements.

App Store descriptionWritten by the developer.

Knock knock. Who's there? Lettuce. Lettuce who? Open the door and find out: a lettuce in earmuffs is standing on your porch, and the punchline lands with a rimshot and a burst of confetti. Knock Knock Simulator is a joke book your kid can play with. Every joke is a proper pun, every visitor is a painted cartoon character, and the punchline only comes when you open the door and see who it is. HOW IT WORKS Tap the big red button and someone knocks. Tap "Who's there?", hear their name through the door, tap "____ who?", then open the door. A yeti who is freezing. An owl in round glasses. BA DUM TISH. Then rate it on the groan meter, from Meh to GROANER! 38 JOKES THAT LAND - Food, animals, names, spooky, holidays, school, silly and the very worst groaners - Every one kid-safe, every one a real pun on the reply, told by a visitor who suits it - A shuffled bag, so you hear every joke before any repeats - Joke of the Day with a streak for coming back - Four stars or more saves a joke to your favourites, ready to tell again SAY IT OUT LOUD Turn on voice mode and the door listens for "Who's there?" and "... who?" Your kid says it, the visitor answers. Recognition happens on the phone: nothing is recorded, nothing is sent anywhere, and voice mode stays off until a grown-up turns it on. Tapping works just as well. ON IPHONE DUO The hinge is the door. Shut the phone and the cover screen is the inside of your front door: knock on it and whoever is outside knocks back (try shave-and-a-haircut), or peek through the peephole to see who is waiting. Open the phone and the punchline is on the porch. On every other iPhone the screen is the door: swipe it open on its hinges and swipe it shut. MORE AT THE DOOR - Party mode: the phone shows you what to say, a friend answers, then you open the door to show them who it was - My Jokes: write your own who and punchline, pick the visitor, share it as a picture (behind a grown-up question) - Six painted front doors, and a porch that changes with the month, after dark, and for the holidays - Kids mode for the littlest: simple jokes and friendly visitors only - Read-aloud voices built in, and adjustable text size FOR GROWN-UPS No ads, no in-app purchases, no accounts, no tracking, no internet needed. Works in the car, on the plane and in the waiting room. Sharing and voice sit behind a grown-up question. One price, every joke in the box. Just corny jokes and a door.

Knock Knock Simulator on iPhone Duo: FAQ

Is Knock Knock Simulator optimized for iPhone Duo?

Yes. Knock Knock Simulator is Built for Duo: it uses the fold, Split View or the outer display. Verified on November 13, 2026 (Developer statement).

What does Knock Knock Simulator look like on iPhone Duo?

When closed, the cover shows the inside of the door and lets you knock or peek. Open the Duo to reveal the visitor and punchline.

How much does Knock Knock Simulator cost?

Knock Knock Simulator costs $1.99 on the App Store.

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