# AO Surgery Reference vs RezClock

The clearest difference is review sentiment: AO Surgery Reference at 86% against RezClock's 0%. AO Surgery Reference also leads on rating (4.4 vs 2.3) and in-app purchases (none vs 1). RezClock's advantage is iOS requirement (10.0 vs 13.0). On price, ads and device support there is nothing between them.

Both are free to download. RezClock sells 1 in-app purchase, starting at $0.99 per month. AO Surgery Reference asks for nothing beyond the download.

AO Surgery Reference holds the better App Store score, 4.4 against 2.3. Both are backed by a comparable volume of ratings — 14 and 3 respectively. Written reviews point the same way: 86% of AO Surgery Reference's written reviews are positive against 0% of RezClock's.

AO Surgery Reference ships an update every 6 months, RezClock every 35 months. The most recent releases landed on October 11, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | AO Surgery Reference | RezClock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (14 ratings)](https://appshunter.io/ios/app/ao-surgery-reference/id403961165/reviews)** | [2.3 (3 ratings)](https://appshunter.io/ios/app/rezclock/id988755622/reviews) |
| Number of ratings | **14** | 3 |
| Positive reviews | **85.8% of reviews** | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 6 months** | Every 35 months |
| Monetization | **Free** | Subscription |
| Size | 1 MB | 24 MB |
| Requires iOS | 13.0 | **10.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 4+ |
| Developer | [AO Foundation](https://appshunter.io/developer/399757056) | [Mitra U.S. Computer Solutions, Inc](https://appshunter.io/developer/988434177) |

## What reviewers say

### AO Surgery Reference

[App page](https://appshunter.io/ios/app/ao-surgery-reference/id403961165)

Access a comprehensive online repository of surgical knowledge for fracture management. It provides detailed guidance on diagnosis, treatment, and aftercare for numerous fracture types, supported by extensive illustrations and expert review.

**Highlights:** 353 fracture types covered, 172 surgical approaches, 1222 surgical procedures, Over 30,000 illustrations, Feline, canine, and equine fracture care, Powerful search function

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

**In-app purchases:** none


### RezClock

[App page](https://appshunter.io/ios/app/rezclock/id988755622)

Automates medical resident duty hour tracking using location services to log arrival and departure times at clinical sites. Hours can be uploaded to other systems for generating ACGME required reports. Offers a free trial period before subscription.

**Highlights:** Automated time tracking, Location-based geofencing, Duty hours reporting, Data upload to MedProSuite, Free trial period

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| RezClock Monthly - $0.99/month | $0.99 | per month |


## Frequently asked questions

### Is AO Surgery Reference free?

AO Surgery Reference is free to download, with no in-app purchases.

### Is RezClock free?

RezClock is free to download, with in-app purchases available.

### Which has better reviews, AO Surgery Reference or RezClock?

AO Surgery Reference is rated higher. AO Surgery Reference averages 4.4 out of 5 from 14 ratings, while RezClock averages 2.3 from 3 ratings.

### Do AO Surgery Reference or RezClock have ads?

Neither AO Surgery Reference nor RezClock shows ads.

### Which is updated more often, AO Surgery Reference or RezClock?

AO Surgery Reference ships an update every 6 months, and RezClock every 35 months. Most recently, AO Surgery Reference was updated on October 11, 2026 and RezClock on October 2, 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.*