# Semantic Segmentation vs Underlayer

The clearest difference is in-app purchases: Semantic Segmentation at none against Underlayer's 1. Semantic Segmentation also leads on update cadence (every 11 days vs every 5 months). Underlayer's advantage is device support (3 vs 1) and iOS requirement (15.1 vs 17.7.2). On price and ads there is nothing between them.

Both are free to download. Underlayer sells 1 in-app purchase, starting at $2.99 per 7 days. Semantic Segmentation asks for nothing beyond the download.

Semantic Segmentation ships an update every 11 days, Underlayer every 5 months. The most recent releases landed on August 4, 2026 and September 12, 2026 respectively.

## The numbers

| Metric | Semantic Segmentation | Underlayer |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | **Every 11 days** | Every 5 months |
| Size | 159 MB | 169 MB |
| Requires iOS | 17.7.2 | **15.1** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Hideaki Uchikoshi](https://appshunter.io/developer/1559575002) | [Mihail Rukavishnikov](https://appshunter.io/developer/1648782212) |

## What reviewers say

### Semantic Segmentation

[App page](https://appshunter.io/ios/app/semantic-segmentation/id6511210084)

**Features:** macOS Compatibility

**In-app purchases:** none


### Underlayer

[App page](https://appshunter.io/ios/app/underlayer/id6753363956)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $2.99 | per 7 days |


## Frequently asked questions

### Is Semantic Segmentation free?

Semantic Segmentation is free to download, with no in-app purchases.

### Is Underlayer free?

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

### Do Semantic Segmentation or Underlayer have ads?

Both Semantic Segmentation and Underlayer show ads.

### Which is updated more often, Semantic Segmentation or Underlayer?

Semantic Segmentation ships an update every 11 days, and Underlayer every 5 months. Most recently, Semantic Segmentation was updated on August 4, 2026 and Underlayer on September 12, 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.*