Simple Negative Image vs Undertone Tuner
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Simple Negative Image
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.
- Invert image colors
- Create unique images
- Generate art-like visuals
- Process images easily
- Invert negatives and positives
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A simple function application that only inverts the color of the image By inverting colors and inverting negatives and positives, you can create unique images and tasteful art-like images. For those who want to process images easily
Undertone Tuner
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.
- Removes redness from fresh tattoos
- Preserves natural skin tone
- Maintains tattoo detail
- On-device processing
- Full-resolution export
- Adjustable strength and threshold
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Undertone is a precision tool for tattoo artists and clients. Fresh tattoos often come with redness and inflammation that can distract from the actual work. Undertone removes that redness while keeping the skin tone and tattoo detail intact. How it works: Select or take a photo of a fresh tattoo. Paint over healthy skin near the tattoo to set a reference tone. Tap Apply. Undertone uses Lab color space analysis to neutralize redness across the image. Fine-tune with Strength, Threshold, and Brightness sliders. Use the Exclude brush to protect specific areas from correction. Save the final image at full camera resolution. Why Undertone: Maintains natural skin tone with precision color math Works with all skin tones Full-resolution export: no quality loss 100% on-device processing. Your photos are never uploaded No accounts, no ads, no tracking Pinch to zoom for detailed work Undo support and before/after toggle Works on iPhone and iPad Built by a tattoo artist, for tattoo artists.
Screenshots
Verdict
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.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
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.
| Parameter | Simple Negative Image | Undertone Tuner |
|---|---|---|
| Price | Free | Free |
| Rating | 4.5 (121 ratings) | 5.0 (2 ratings) — better |
| Positive reviews | 56.3% of reviews | 100.0% of reviews — better |
| Number of ratings | 121 — better | 2 |
| Update frequency | Every 2 months | Monthly — better |
| Ads | Yes | No — better |
| In-app purchases | No — better | Yes |
| Monetization | Ad-supported | Free — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.6 | 15.1 — better |
| Further details — not scored | ||
| Size | 34 MB | 31 MB |
| Age rating | 4+ | 4+ |
| Developer | Ryouhei Azuma | Inner Circle |
Customer experience
Simple Negative Image
Undertone Tuner
In-app purchases
Simple Negative Image
No in-app purchases
Undertone Tuner
- Continue Support$4.99
- Sustain Support$12.99
Questions
Is Simple Negative Image free?
Is Undertone Tuner free?
Which has better reviews, Simple Negative Image or Undertone Tuner?
Do Simple Negative Image or Undertone Tuner have ads?
Which is updated more often, Simple Negative Image or Undertone Tuner?
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