Hertz Sense
Match the Hz with your wrist
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Pick a Hz target and match it using gentle wrist motion. 100% offline, no ads, no tracking. Play solo or compete with family and friends for best accuracy.
Hertz Sense is a rhythm-sense mini-game that measures how accurately you can match a target frequency (Hz) using gentle wrist motion only.
■ How to Play
1. Pick a target from 0.5 / 1.0 / 1.5 Hz (or set a custom value in 0.1 Hz steps)
2. Press START — a 3 → 2 → 1 → GO countdown begins
3. Move your iPhone left and right with gentle WRIST MOTION ONLY for 5 seconds
4. The result screen shows your measured Hz, the delta from target, and a graph comparing your motion vs the target
■ Features
- Capped at 1.5 Hz — gentle wrist motion only, no full-arm shaking
- Built-in safety auto-stop if excessive motion is detected
- Mandatory safety guide on first launch
- Two visual themes: Cyber (neon hacker style) and Soft (calm cream)
- Bilingual (Japanese / English) with kid-friendly explanation of frequency
- Fully offline — no network access required
■ Play Safely
- Hold the iPhone firmly with one hand (a wrist strap is recommended)
- Use only your WRIST — do not swing your arm
- Do not use while walking or running
- Play in an open space with no people or objects nearby
A fun way to experience the physics concept of "frequency" with your own body — works well as a learning aid for students too.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
- Greatly improved frequency measurement accuracy. Readings that previously came out lower than your actual shake are now correct, so "Perfect!" is properly achievable
- When a shake can't be measured, the app now says so instead of showing a number
- Changed the minimum custom frequency to 0.4 Hz (lower values can't be measured accurately within 5 seconds)
- The result screen and custom frequency screen now support Japanese
- Fixed voice playing even when both music and sound effects were turned off
- Fixed the app interrupting music from other apps on launch
- Measurement is now cancelled if you switch away from the app mid-measurement
- Improved the layout of the safety agreement screen
- Other minor display fixes
The developer, seiji honda, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- seiji honda
- Size
- 2.5 MB
- Category
- Casual
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- Japanese
- Age Rating
4+
- 4+
- Copyright
- © Seiji Honda