# Preop Eval vs Know HBV

The clearest difference is rating: Preop Eval at 5.0 against Know HBV's 4.3. Know HBV's advantage is review sentiment (100% vs 67%) and device support (3 vs 1). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Preop Eval holds the better App Store score, 5.0 against 4.3. Both are backed by a comparable volume of ratings — 2 and 3 respectively. Written reviews complicate that: 67% of Preop Eval's written reviews are positive against 100% of Know HBV's, so the app with the better star average is not the one people write more warmly about.

Preop Eval ships an update every 6 months, Know HBV every 4 months. The most recent releases landed on September 30, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | Preop Eval | Know HBV |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/preop-eval/id374154834/reviews)** | [4.3 (3 ratings)](https://appshunter.io/ios/app/know-hbv/id1523455855/reviews) |
| Number of ratings | 2 | **3** |
| Positive reviews | 66.7% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 4 months** |
| Monetization | Free | Free |
| Size | 15 MB | 67 MB |
| Requires iOS | 16.6 | **12.0** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 17+ | 17+ |
| Developer | [United Health Services, Inc.](https://appshunter.io/developer/1451318916) | [Hep B Moms](https://appshunter.io/developer/1519551534) |

## What reviewers say

### Preop Eval

[App page](https://appshunter.io/ios/app/preop-eval/id374154834)

This app provides guidance for evaluating and preparing adult patients for non-cardiac surgery. It includes algorithms and resources on medication management, cardiac event timing, and preoperative testing, serving as both a reference and a teaching tool for medical professionals.

**Highlights:** Cardiac evaluation algorithm, Medication guidance (starting/stopping), Surgery timing after cardiac events, Preoperative testing recommendations, Review for students and residents, Perioperative insulin management

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

**In-app purchases:** none


### Know HBV

[App page](https://appshunter.io/ios/app/know-hbv/id1523455855)

This educational tool assists primary healthcare professionals in managing adults with chronic hepatitis B. It offers guidance on monitoring and recommends antiviral treatment based on WHO and AASLD guidelines. It is intended for healthcare providers and not for patient self-diagnosis or treatment decisions.

**Highlights:** Chronic hepatitis B monitoring guidance, Antiviral treatment recommendations, WHO and AASLD guideline adaptation, Educational tool for healthcare professionals, Resource-limited country focus

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Preop Eval free?

Preop Eval is free to download, with no in-app purchases.

### Is Know HBV free?

Know HBV is free to download, with no in-app purchases.

### Which has better reviews, Preop Eval or Know HBV?

Preop Eval is rated higher. Preop Eval averages 5.0 out of 5 from 2 ratings, while Know HBV averages 4.3 from 3 ratings.

### Do Preop Eval or Know HBV have ads?

Neither Preop Eval nor Know HBV shows ads.

### Which is updated more often, Preop Eval or Know HBV?

Preop Eval ships an update every 6 months, and Know HBV every 4 months. Most recently, Preop Eval was updated on September 30, 2026 and Know HBV on October 1, 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.*