# Dermoscopy Two Step Algorithm vs Derm DDx

The clearest difference is in-app purchases: Dermoscopy Two Step Algorithm at none against Derm DDx's 1. Dermoscopy Two Step Algorithm also leads on rating (4.6 vs 4.3) and iOS requirement (10.0 vs 15.0). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. Derm DDx sells 1 one-off in-app purchase. Dermoscopy Two Step Algorithm asks for nothing beyond the download.

Dermoscopy Two Step Algorithm holds the better App Store score, 4.6 against 4.3. Both are backed by a comparable volume of ratings — 10 and 6 respectively.

Both ship on a similar rhythm, roughly every 5 months. The most recent releases landed on October 7, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | Dermoscopy Two Step Algorithm | Derm DDx |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (10 ratings)](https://appshunter.io/ios/app/dermoscopy-two-step-algorithm/id731753300/reviews)** | [4.3 (6 ratings)](https://appshunter.io/ios/app/derm-ddx/id6499524221/reviews) |
| Number of ratings | **10** | 6 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | Every 5 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 220 MB | 10 MB |
| Requires iOS | **10.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 17+ |
| Developer | [Usatine & Erickson Media LLC](https://appshunter.io/developer/1466894388) | [Unbound Medicine, Inc.](https://appshunter.io/developer/300420400) |

## What reviewers say

### Dermoscopy Two Step Algorithm

[App page](https://appshunter.io/ios/app/dermoscopy-two-step-algorithm/id731753300)

This app guides healthcare professionals in interpreting dermoscopic patterns to identify skin lesions. It uses a series of questions and provides over 80 images and charts to aid in diagnosis. Interactive cases are included for practice.

**Highlights:** Dermoscopic pattern interpretation, Question-based diagnostic guidance, Over 80 photos and charts, 50 interactive diagnostic cases, Offline functionality, Melanocytic and non-melanocytic lesion analysis

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

**In-app purchases:** none


### Derm DDx

[App page](https://appshunter.io/ios/app/derm-ddx/id6499524221)

This app provides visual, point-of-care guidance for diagnosing skin disorders. It features a large database of high-resolution images, allowing users to compare variations, zoom in, and access clinical history and treatment options for over 160 dermatologic conditions.

**Highlights:** 650+ high-quality dermatology images, Guidance for 160+ dermatologic conditions, Side-by-side image variations, Zoomable high-resolution images, Clinical history and treatment options, Cross-referencing to differential diagnoses, Full text search and custom notes

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Dermatology DDx | $69.99 | one-time |


## Frequently asked questions

### Is Dermoscopy Two Step Algorithm free?

Dermoscopy Two Step Algorithm is free to download, with no in-app purchases.

### Is Derm DDx free?

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

### Which has better reviews, Dermoscopy Two Step Algorithm or Derm DDx?

Dermoscopy Two Step Algorithm is rated higher. Dermoscopy Two Step Algorithm averages 4.6 out of 5 from 10 ratings, while Derm DDx averages 4.3 from 6 ratings.

### Do Dermoscopy Two Step Algorithm or Derm DDx have ads?

Neither Dermoscopy Two Step Algorithm nor Derm DDx shows ads.

### Which is updated more often, Dermoscopy Two Step Algorithm or Derm DDx?

Dermoscopy Two Step Algorithm ships an update every 5 months, and Derm DDx every 5 months. Most recently, Dermoscopy Two Step Algorithm was updated on October 7, 2026 and Derm DDx on October 11, 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.*