# VisualDx vs STI Tx Guide

The clearest difference is review sentiment: VisualDx at 84% against STI Tx Guide's 36%. VisualDx also leads on rating (4.4 vs 3.5) and update cadence (fortnightly vs every 2 months). STI Tx Guide's advantage is in-app purchases (none vs 11). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. VisualDx sells 11 in-app purchases, starting at $39.99 per month. STI Tx Guide asks for nothing beyond the download.

VisualDx holds the better App Store score, 4.4 against 3.5. That said, the two scores are not equally well evidenced: VisualDx has 186 ratings behind it against 36, so its average is the more settled of the two. Written reviews point the same way: 84% of VisualDx's written reviews are positive against 36% of STI Tx Guide's.

VisualDx ships an update fortnightly, STI Tx Guide every 2 months. The most recent releases landed on September 23, 2026 and August 28, 2026 respectively.

## The numbers

| Metric | VisualDx | STI Tx Guide |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (186 ratings)](https://appshunter.io/ios/app/visualdx/id348177521/reviews)** | [3.5 (36 ratings)](https://appshunter.io/ios/app/sti-tx-guide/id655206856/reviews) |
| Number of ratings | **186** | 36 |
| Positive reviews | **84.3% of reviews** | 35.7% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | Subscription | **Free** |
| Best chart rank | **#11** | — |
| Size | 226 MB | 36 MB |
| Requires iOS | 16.4 | **15.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 17+ | 12+ |
| Developer | [Logical Images](https://appshunter.io/developer/348177524) | [Centers For Disease Control and Prevention](https://appshunter.io/developer/439259253) |

## What reviewers say

### VisualDx

[App page](https://appshunter.io/ios/app/visualdx/id348177521)

**Currently charting:** #11 Top Grossing · Medical (US App Store)

This visual reference tool aids medical professionals in improving patient engagement and diagnostic accuracy. It utilizes AI and a vast image atlas to help build custom differentials, share patient-specific images, and access comprehensive diagnostic information. Earn continuing education credits while making better medical decisions.

**Highlights:** Build custom differentials, Engage patients with visual aids, Improve diagnostic accuracy, Access therapy and test options, Recognize infectious diseases, Earn CME credits

**In-app purchases (11)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Complete (1 Month) | $39.99 | per month |
| VisualDx Core Monthly | $39.99 | per month |
| Complete+DermExpert (1 Month) | $49.99 | per month |
| VisualDx Elite Monthly | $49.99 | per month |
| Add DermExpert (1 Year) | $99.99 | per year |
| Complete (1 Year) | $149.99 | per year |
| VisualDx Core Annual | $249.99 | per year |
| VisualDx Elite Annual | $299.99 | per year |
| Complete+DermExpert (1 Year) | $499.99 | per year |
| Add DermExpert (1 yr) | $99.99 | one-time |
| Complete (1 yr) | $399.99 | one-time |

**What reviewers like**

- 📸 Excellent clinical images and kodachromes
- 👍 User-friendly interface and easy navigation
- 🎓 Comprehensive differential diagnosis tool
- 📚 Detailed disease summaries and treatment information
- 🌍 Inclusive representation of skin of color

**What reviewers complain about**

- 💰 Expensive subscription cost
- ❌ Difficult subscription cancellation process
- 🐛 App crashes and performance issues
- 📱 Quiz feature laggy and unreliable
- 😤 Poor customer service responsiveness

**Reported bugs**

- App crashes when using quiz feature
- CME credit claiming functionality fails
- Subscription cancellation not processed
- Renewal charges despite cancellation requests
- Quiz unable to load properly

**Requested features**

- Make app free again (previously free)
- Simplify subscription cancellation in-app
- Improve quiz functionality for mobile
- Add quiz feature to desktop version
- Expand patient information handouts


### STI Tx Guide

[App page](https://appshunter.io/ios/app/sti-tx-guide/id655206856)

Provides healthcare professionals with up-to-date, evidence-based recommendations for the prevention, diagnosis, and treatment of sexually transmitted infections. Features include clinical care guidance, sexual history resources, and patient materials for effective patient management.

**Highlights:** STI prevention recommendations, Diagnosis guidance, Treatment protocols, Clinical care assistance, Sexual history resources, Patient management tools

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

**In-app purchases:** none


## Frequently asked questions

### Is VisualDx free?

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

### Is STI Tx Guide free?

STI Tx Guide is free to download, with no in-app purchases.

### Which has better reviews, VisualDx or STI Tx Guide?

VisualDx is rated higher. VisualDx averages 4.4 out of 5 from 186 ratings, while STI Tx Guide averages 3.5 from 36 ratings.

### Do VisualDx or STI Tx Guide have ads?

Neither VisualDx nor STI Tx Guide shows ads.

### Which is updated more often, VisualDx or STI Tx Guide?

VisualDx ships an update fortnightly, and STI Tx Guide every 2 months. Most recently, VisualDx was updated on September 23, 2026 and STI Tx Guide on August 28, 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.*