Janken Referee

Hold your hands up to the camera and Janken Lens calls the winner instantly. All processing is on-device — no image leaves your iPhone. Great for play and learning.

Janken Referee recognizes hand gestures (rock, scissors, paper) in real time through your iPhone's camera and automatically calls the winner of a rock-paper-scissors match. ("Janken" is the Japanese word for rock-paper-scissors.)

■ Highlights

• Just point the camera at two or more hands — the winner is called automatically
• Winning hands are highlighted in a distinct color for instant clarity • 100% on-device processing. No camera frame ever leaves your iPhone • Free, no ads, no account required

■ How People Use It

• Settle a rock-paper-scissors match between family or friends instantly • Works with three or more players, not just two • A teaching aid in classrooms and childcare settings
• A novelty effect for streams and video content

■ Privacy by Design

Janken Referee is built with user privacy as the top priority.

• Camera frames are processed exclusively on-device using Apple Vision
• No camera data, detection result, or other information is transmitted to any external server • No analytics SDK, no advertising SDK, no tracking of any kind • No personal information is collected

■ Misclassification Reports (Opt-In)

Janken Referee includes an optional feature that lets you send a report to the developer when a judgment was incorrect, helping improve future accuracy.

• Disabled by default. Active only when explicitly enabled in Settings
• Reports stay on your device unless you explicitly send them via the iOS Mail app • The recipient address is always visible in Settings before you export
• Up to 50 reports are stored locally; oldest reports are removed automatically • You can delete reports individually or all at once at any time

■ System Requirements

• iOS 16.6 or later • Camera access required • Photo Library "Add Only" access required only when saving images

■ Support and Contact

For questions, feature requests, or bug reports:
jankenlens@gmail.com

Privacy Policy: https://grave-amphibian-76f.notion.site/Privacy-Policy-371cb437852d80459c5cd68c0408cf4c

Support: https://grave-amphibian-76f.notion.site/Support-371cb437852d808a861dd545ac19aec5