# Protozoan Identification vs Learn Digestive System

The clearest difference is price: Protozoan Identification at Free against Learn Digestive System's $2.99. Protozoan Identification also leads on update cadence (every 15 months vs every 36 months). Learn Digestive System's advantage is iOS requirement (11.0 vs 13.0). On ads, in-app purchases and device support there is nothing between them.

Protozoan Identification is free to download; Learn Digestive System costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Protozoan Identification ships an update every 15 months, Learn Digestive System every 36 months. The most recent releases landed on June 5, 2026 and August 13, 2026 respectively.

## The numbers

| Metric | Protozoan Identification | Learn Digestive System |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | **[2.0 (1 ratings)](https://appshunter.io/ios/app/protozoan-identification/id506715288/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 15 months** | Every 36 months |
| Monetization | Free | — |
| Size | 221 MB | 14 MB |
| Requires iOS | 13.0 | **11.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 12+ |
| Developer | [Carolina Biological Supply](https://appshunter.io/developer/413708533) | [Nurten PIRLI](https://appshunter.io/developer/1495958705) |

## What reviewers say

### Protozoan Identification

[App page](https://appshunter.io/ios/app/protozoan-identification/id506715288)

Explore a collection of protozoan images and videos. Features an interactive key, labeling activities, and practice exercises to aid in identification and study.

**Highlights:** Interactive dichotomous key, Labeling activities, Protozoan images and videos, Practice exercises, Study aids

**Features:** macOS Compatibility

**In-app purchases:** none


### Learn Digestive System

[App page](https://appshunter.io/ios/app/learn-digestive-system/id1502378106)

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

**In-app purchases:** none


## Frequently asked questions

### Is Protozoan Identification free?

Protozoan Identification is free to download, with no in-app purchases.

### Is Learn Digestive System free?

Learn Digestive System costs $2.99, with no in-app purchases.

### Do Protozoan Identification or Learn Digestive System have ads?

Neither Protozoan Identification nor Learn Digestive System shows ads.

### Which is updated more often, Protozoan Identification or Learn Digestive System?

Protozoan Identification ships an update every 15 months, and Learn Digestive System every 36 months. Most recently, Protozoan Identification was updated on June 5, 2026 and Learn Digestive System on August 13, 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.*