# Human Digestive System vs Direct Proportion

The clearest difference is price: Direct Proportion at Free against Human Digestive System's $0.99. Direct Proportion also leads on device support (3 vs 1). On ads, in-app purchases and iOS requirement there is nothing between them.

Direct Proportion is free to download; Human Digestive System costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | Human Digestive System | Direct Proportion |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 18 months | — |
| Size | 401 MB | 50 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [www.ajaxmediatech.com](https://appshunter.io/developer/973768003) | [Science Education Institute](https://appshunter.io/developer/1439710468) |

## What reviewers say

### Human Digestive System

[App page](https://appshunter.io/ios/app/human-digestive-system/id983535092)

**Features:** macOS Compatibility

**In-app purchases:** none


### Direct Proportion

[App page](https://appshunter.io/ios/app/direct-proportion/id6736588837)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Human Digestive System free?

Human Digestive System costs $0.99, with no in-app purchases.

### Is Direct Proportion free?

Direct Proportion is free to download, with no in-app purchases.

### Do Human Digestive System or Direct Proportion have ads?

Neither Human Digestive System nor Direct Proportion shows ads.

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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.*