# Simple Negative Image vs Undertone Tuner

The clearest difference is review sentiment: Undertone Tuner at 100% against Simple Negative Image's 56%. Undertone Tuner also leads on ads (none vs shown) and rating (5.0 vs 4.5). Simple Negative Image's advantage is in-app purchases (none vs 2) and ratings volume (121 vs 2). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Undertone Tuner sells 2 one-off in-app purchases. Simple Negative Image asks for nothing beyond the download.

Undertone Tuner holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: Simple Negative Image has 121 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 56% of Simple Negative Image's written reviews are positive against 100% of Undertone Tuner's.

Simple Negative Image ships an update every 2 months, Undertone Tuner monthly. The most recent releases landed on October 21, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | Simple Negative Image | Undertone Tuner |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (121 ratings)](https://appshunter.io/ios/app/simple-negative-image/id6444569227/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/undertone-tuner/id6759796106/reviews)** |
| Number of ratings | **121** | 2 |
| Positive reviews | 56.3% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 2 months | **Monthly** |
| Monetization | Ad-supported | **Free** |
| Size | 34 MB | 31 MB |
| Requires iOS | 15.6 | **15.1** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Ryouhei Azuma](https://appshunter.io/developer/1353297781) | [Inner Circle](https://appshunter.io/developer/367838600) |

## What reviewers say

### Simple Negative Image

[App page](https://appshunter.io/ios/app/simple-negative-image/id6444569227)

Easily invert image colors to create unique artistic effects. This tool allows for the inversion of negatives and positives, transforming ordinary photos into tasteful art-like creations. Perfect for users seeking straightforward image processing.

**Highlights:** Invert image colors, Create unique images, Generate art-like visuals, Process images easily, Invert negatives and positives

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

**In-app purchases:** none


### Undertone Tuner

[App page](https://appshunter.io/ios/app/undertone-tuner/id6759796106)

This tool helps tattoo artists and clients visualize healed tattoos by removing redness and inflammation from fresh ink. It preserves skin tone and tattoo detail, offering precise adjustments and full-resolution export.

**Highlights:** Removes redness from fresh tattoos, Preserves natural skin tone, Maintains tattoo detail, On-device processing, Full-resolution export, Adjustable strength and threshold

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Continue Support | $4.99 | one-time |
| Sustain Support | $12.99 | one-time |


## Frequently asked questions

### Is Simple Negative Image free?

Simple Negative Image is free to download, with no in-app purchases.

### Is Undertone Tuner free?

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

### Which has better reviews, Simple Negative Image or Undertone Tuner?

Undertone Tuner is rated higher. Simple Negative Image averages 4.5 out of 5 from 121 ratings, while Undertone Tuner averages 5.0 from 2 ratings.

### Do Simple Negative Image or Undertone Tuner have ads?

Simple Negative Image shows ads; Undertone Tuner does not.

### Which is updated more often, Simple Negative Image or Undertone Tuner?

Simple Negative Image ships an update every 2 months, and Undertone Tuner monthly. Most recently, Simple Negative Image was updated on October 21, 2026 and Undertone Tuner 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.*