Life-size AR ruler
Place the ruler from the mouth to the end of the tail, then adjust its position and direction before capture.
PRODUCT / IOSIn Development
GYOSUN
魚寸Measure the fish. Keep the catch.
GYOSUN places a life-size AR ruler beside a fish, then saves the marked photo and catch details on your iPhone. No reference card or dedicated measuring board needs to appear in the photo.
The app is a free download with five AR captures included. GYOSUN Complete is a one-time purchase, priced at ¥1,800 on the Japan App Store.
This is the official GYOSUN app icon. Device screenshots will be added after the App Store screenshot set is finalized.
Overview
Complete the record at the water.
Measure, photograph, and save the details of a catch in one flow. In-app records remain available on your iPhone even where there is no network connection.
GYOSUN keeps more than a number. A life-size ruler remains visible in the saved photo, so you can review the measurement and the catch together later.
Marked catch photo
Keep the ruler in the image so the context behind the recorded measurement remains visible.
On-device records
Store the photo, species, size, date, location, and notes on your iPhone without sending them to a WATARI CROSS server.
From measurement to record
Detect a surface
Place the fish on a flat surface and move the camera slowly so the surrounding surface can be detected.
Align the ruler
Mark the mouth and the end of the tail, then check and adjust the displayed ruler.
Capture and save
Take the marked photo, review the species, date, optional location, and notes, then save the catch.
Requirements
- Designed for ARKit-compatible iPhones only.
- Camera access is required for AR measurement and capture.
- Location access is optional. Catches can be saved without a location.
- Requires iOS 17.0 or later.
ACCURACY
About measurement results
GYOSUN measurements are reference estimates based on ARKit surface detection and ruler placement. Device, lighting, surface texture, and camera angle can affect accuracy.
For tournaments, record applications, sales, or any use that requires an official measurement, use a physical measuring device approved for that purpose.
PRIVACY BY DESIGN
Keep the catch. Not on our server.
GYOSUN has no account registration and no WATARI CROSS server for catch records. Apple backup and photo sync follow your device settings.
Read the privacy policyD-01
Catch data and photos are stored in the app's private area on your device.
D-02
The GYOSUN app includes no advertising SDK or independent analytics SDK.
D-03
Location is used only when you choose to attach a place to a catch.
D-04
Depending on device settings, catch data may be included in an iCloud backup.
D-05
Images saved to Photos are managed separately from catches in the app.
Access
Try the complete product for five captures, then choose the one-time Complete upgrade only if you need it. Free captures have no watermark or intentional quality reduction.
P-1
The first five AR captures are free
P-2
GYOSUN Complete is a one-time purchase
P-3
Complete unlocks unlimited AR captures and catch records after the first five
P-4
No advertising
P-5
No subscription
The current Japan App Store price is ¥1,800. Prices may vary by region or later App Store pricing changes; check the price shown by the App Store before purchase.
Support
Review the answers below for help with common issues. If the problem continues, email us with your device and the steps that led to the issue.
Frequently asked questions
The AR ruler does not appear.
Use a bright, flat area with visible texture and move the iPhone slowly. Surface detection can take longer in low light or over a featureless surface.
Is location access required?
No. You can measure, capture, and save a catch without attaching a location.
Where are my records stored?
Photos and catch information are stored in the app's private area on your iPhone and are not sent to a WATARI CROSS server.
What happens if I delete the app?
Catch data in the app's private storage is removed from the device. The free-capture count and last verified purchase status may remain in Keychain. Photos-library copies, iCloud backups, and App Store purchase records are managed separately.
Can I use a result as an official measurement?
Measurements are reference estimates. Use a physical measuring device approved for any purpose that requires an official result.