---
title: "OKN Viewer: Nystagmus - Reviews, Revenue and Downloads in United States | Apple App Store"
description: "Even in healthy people, nystagmus naturally occurs when watching moving scenery. This app reproduces that nystagmus on your smartphone screen and lets you record your eye movements with the front-faci"
---

# OKN Viewer: Nystagmus — United States
> Observe Optokinetic Nystagmus

![OKN Viewer App Icon](https://is1-ssl.mzstatic.com/image/thumb/Purple211/v4/24/06/1d/24061dfa-0ac2-c574-5311-538e909d9121/AppIcon-0-0-1x_U007epad-0-1-85-220.jpeg/434x0w.png)

**Developer:** [ishida yuto](https://apptail.io/developer/ishida-yuto-Lmhb)
**Category:** Medical
**Rating:** 3.7/5 (3 ratings)
**Price:** Free
**Bundle ID:** com.ishida.isihda.nystagmusTest
**Store:** Apple App Store
**Country:** United States
**Version:** 1.4 (released 2026-02-19)
**Original Release:** 2024-09-19
**Languages:** Japanese, English

**App Store Link:** [Download on Apple App Store](https://apps.apple.com/us/app/app/id6695726882)
**AppTail Page:** [https://apptail.io/app/okn-viewer-nystagmus-KdEt/united-states](https://apptail.io/app/okn-viewer-nystagmus-KdEt/united-states)

## OKN Viewer Description
Even in healthy people, nystagmus naturally occurs when watching moving scenery.
This app reproduces that nystagmus on your smartphone screen and lets you record your eye movements with the front-facing camera — a simple tool to observe and experience nystagmus.

By staring at the moving stripe pattern (bands) on the screen, you can easily observe optokinetic nystagmus (OKN).
It can be used as a preview/review tool in medical, rehabilitation, and educational settings, and also answers the simple question:
“What does nystagmus actually look like?”


【Main Features】

• Adjustable stripe width
Change the width of the moving stripes intuitively with a slider.

• Adjustable moving speed
Freely set how fast the stripes move, from very slow to fast.

• Customizable stripe color
Choose colors that suit your preference and visibility to enhance the visual effect.

• Record eye movements with the front camera
Keep your gaze fixed on the screen and record your eye movements, then review them later.


【Recommended For】

• Those who want to deepen their understanding of nystagmus and optokinetic nystagmus (OKN):
physicians, medical students, orthoptists, nurses, rehabilitation staff, and clinical laboratory technologists.

• Teachers and instructors looking for an easy-to-use visual teaching material for classes, practical training, or lectures.

• Science- and medicine-oriented students, as well as general users who are interested in visual effects and how the body reacts to them.



• No advertisements



Important Notice

This app is designed as a tool for observing, learning about, and experiencing nystagmus and optokinetic nystagmus.
It is not a medical device and is not intended for diagnosis or treatment.

If you have any symptoms or concerns and need evaluation, diagnosis, or treatment, please consult a physician or other qualified healthcare professional.

## OKN Viewer Screenshots
- [Screenshot 1](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/01/0c/5e/010c5eaf-6542-b5d4-e01a-ce76bbf25d2f/Apple_iPhone_11_Pro_Max_Screenshot_1.png/1242x2688.png)
- [Screenshot 2](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/d1/4d/5f/d14d5f4a-c400-c57d-483c-35ac81ac3c9b/Apple_iPhone_11_Pro_Max_Screenshot_2.png/1242x2688.png)
- [Screenshot 3](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/10/e3/c8/10e3c821-06ce-fea1-4c8e-f094bc93fcfa/Apple_iPhone_11_Pro_Max_Screenshot_3.png/1242x2688.png)
- [Screenshot 4](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/0a/38/1d/0a381d6b-8d2a-46b0-a781-075f4ca990fe/Apple_iPhone_11_Pro_Max_Screenshot_5.png/1242x2688.png)
- [Screenshot 5](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/06/7a/f4/067af449-37b9-1eeb-b6a2-04c2850eb164/Apple_iPhone_11_Pro_Max_Screenshot_4.png/1242x2688.png)

## OKN Viewer Rating Breakdown in United States
- 5 stars: 2 (67%)
- 4 stars: 0 (0%)
- 3 stars: 0 (0%)
- 2 stars: 0 (0%)
- 1 stars: 1 (33%)

## OKN Viewer Reviews in United States

### ***** "Nystagmus test"
Very helpful and useful
-- Neuro-ophthalmology, 2025-10-07

[View all OKN Viewer reviews and detailed analytics on AppTail](https://apptail.io/account/signup?utm_campaign=ai-crawl&utm_content=reviews)


## OKN Viewer Store Rankings
| Chart | Country | Category | Rank |
|-------|---------|----------|------|
| Top Paid | Japan | Medical | #230 |
| Top Paid | France | Medical | #239 |
| Top Paid | Ukraine | Medical | #250 |
| Top Paid | Finland | Medical | #267 |
| Top Paid | Germany | Medical | #302 |
| Top Paid | Spain | Medical | #374 |
| Top Paid | Russia | Medical | #404 |
| Top Paid | Austria | Medical | #432 |

## OKN Viewer Discovered Keywords
- okn viewer
- nystagmus


## OKN Viewer Available In
- [United States](https://apptail.io/app/okn-viewer-nystagmus-KdEt/united-states)
- [France](https://apptail.io/app/okn-viewer-nystagmus-KdEt/france)
- [India](https://apptail.io/app/okn-viewer-nystagmus-KdEt/india)
- [Italy](https://apptail.io/app/okn-viewer-nystagmus-KdEt/italy)
- [Japan](https://apptail.io/app/okn-viewer-nystagmus-KdEt/japan)
- [Russia](https://apptail.io/app/okn-viewer-nystagmus-KdEt/russia)
- [Ireland](https://apptail.io/app/okn-viewer-nystagmus-KdEt/ireland)
- [Israel](https://apptail.io/app/okn-viewer-nystagmus-KdEt/israel)
- [Malaysia](https://apptail.io/app/okn-viewer-nystagmus-KdEt/malaysia)
- [Netherlands](https://apptail.io/app/okn-viewer-nystagmus-KdEt/netherlands)
- [Norway](https://apptail.io/app/okn-viewer-nystagmus-KdEt/norway)
- [New Zealand](https://apptail.io/app/okn-viewer-nystagmus-KdEt/new-zealand)
- [Sweden](https://apptail.io/app/okn-viewer-nystagmus-KdEt/sweden)
- [Singapore](https://apptail.io/app/okn-viewer-nystagmus-KdEt/singapore)
- [Ukraine](https://apptail.io/app/okn-viewer-nystagmus-KdEt/ukraine)
- [Vietnam](https://apptail.io/app/okn-viewer-nystagmus-KdEt/vietnam)
- [Austria](https://apptail.io/app/okn-viewer-nystagmus-KdEt/austria)
- [South Africa](https://apptail.io/app/okn-viewer-nystagmus-KdEt/south-africa)
- [Azerbaijan](https://apptail.io/app/okn-viewer-nystagmus-KdEt/azerbaijan)
- [Denmark](https://apptail.io/app/okn-viewer-nystagmus-KdEt/denmark)
- [Dominican Republic](https://apptail.io/app/okn-viewer-nystagmus-KdEt/dominican-republic)
- [Spain](https://apptail.io/app/okn-viewer-nystagmus-KdEt/spain)
- [Finland](https://apptail.io/app/okn-viewer-nystagmus-KdEt/finland)

---

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