# 屈折度数 ORT.com vs Presentation Clock TimeKeeper

The clearest difference is review sentiment: 屈折度数 ORT.com at 100% against Presentation Clock TimeKeeper's 25%. 屈折度数 ORT.com also leads on in-app purchases (none vs 3) and ads (none vs shown). Presentation Clock TimeKeeper's advantage is price (Free vs $0.99) and update cadence (every 3 weeks vs every 39 months). On device support there is nothing between them.

Presentation Clock TimeKeeper is free to download; 屈折度数 ORT.com costs $0.99 up front. Presentation Clock TimeKeeper sells 3 in-app purchases, starting at $1.99 per month. 屈折度数 ORT.com asks for nothing beyond the download.

屈折度数 ORT.com ships an update every 39 months, Presentation Clock TimeKeeper every 3 weeks. The most recent releases landed on October 1, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | 屈折度数 ORT.com | Presentation Clock TimeKeeper |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | — | **[4.9 (14 ratings)](https://appshunter.io/ios/app/presentation-clock-timekeeper/id6449137372/reviews)** |
| Number of ratings | — | **14** |
| Positive reviews | **100.0% of reviews** | 25.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 39 months | **Every 3 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 0 MB | 21 MB |
| Requires iOS | 26.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [kohei yamane](https://appshunter.io/developer/1239055575) | [Jordan Holland](https://appshunter.io/developer/1041851744) |

## What reviewers say

### 屈折度数 ORT.com

[App page](https://appshunter.io/ios/app/ortcom/id1400812675)

This app visualizes refractive errors, from power cross to image formation diagrams. It instantly calculates and displays the main and weak axes of astigmatism, simulates image formation on the retina, and helps distinguish between different types of astigmatism. Ideal for students and professionals in vision training.

**Highlights:** Instant calculation of main and weak astigmatism axes, Visual power cross display, Image formation diagram simulation, Distinguishes astigmatism types, Simple and speedy operation, Ideal for vision training students and professionals

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Presentation Clock TimeKeeper

[App page](https://appshunter.io/ios/app/presentation-clock-timekeeper/id6449137372)

This app helps you manage your speaking time during presentations and speeches. It offers customizable bell sounds and visual indicators to keep you on track and deliver impactful performances.

**Highlights:** Flexible timer management (start, pause, reset), Customizable bell sounds at three intervals, Optional notifications, Visual indicators for time awareness, User-friendly interface, Versatile for speeches, debates, and meetings

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $1.99 | per month |
| Premium | $12.99 | per year |
| Premium | $19.99 | one-time |


## Frequently asked questions

### Is 屈折度数 ORT.com free?

屈折度数 ORT.com costs $0.99, with no in-app purchases.

### Is Presentation Clock TimeKeeper free?

Presentation Clock TimeKeeper is free to download, with in-app purchases available.

### Do 屈折度数 ORT.com or Presentation Clock TimeKeeper have ads?

Presentation Clock TimeKeeper shows ads; 屈折度数 ORT.com does not.

### Which is updated more often, 屈折度数 ORT.com or Presentation Clock TimeKeeper?

屈折度数 ORT.com ships an update every 39 months, and Presentation Clock TimeKeeper every 3 weeks. Most recently, 屈折度数 ORT.com was updated on October 1, 2026 and Presentation Clock TimeKeeper on September 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*