# Interactive Photosynthesis vs Logical Fallacy Memory

The clearest difference is price: Logical Fallacy Memory at Free against Interactive Photosynthesis's $1.99. Logical Fallacy Memory also leads on update cadence (every 2 weeks vs every 25 months). Interactive Photosynthesis's advantage is in-app purchases (none vs 2) and iOS requirement (12.0 vs 17). On ads and device support there is nothing between them.

Logical Fallacy Memory is free to download; Interactive Photosynthesis costs $1.99 up front. Logical Fallacy Memory sells 2 in-app purchases, starting at $1.99 per month. Interactive Photosynthesis asks for nothing beyond the download.

Interactive Photosynthesis ships an update every 25 months, Logical Fallacy Memory every 2 weeks. The most recent releases landed on November 7, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | Interactive Photosynthesis | Logical Fallacy Memory |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | — | **[1.0 (1 ratings)](https://appshunter.io/ios/app/logical-fallacy-memory/id6484316242/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 25 months | **Every 2 weeks** |
| Monetization | — | Free with in-app purchases |
| Size | 183 MB | 7 MB |
| Requires iOS | **12.0** | 17 |
| Devices | iPad, Apple TV | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Ventura Educational Systems](https://appshunter.io/developer/371324172) | [山 汪](https://appshunter.io/developer/1740449088) |

## What reviewers say

### Interactive Photosynthesis

[App page](https://appshunter.io/ios/app/interactive-photosynthesis/id1511209024)

**Features:** macOS Compatibility

**In-app purchases:** none


### Logical Fallacy Memory

[App page](https://appshunter.io/ios/app/logical-fallacy-memory/id6484316242)

Master common logical fallacies and enhance your critical thinking skills. This app uses active recall and spaced repetition to help you identify reasoning errors in real-world situations. Track your progress with a personalized mastery map and learn over 60 unique fallacies.

**Highlights:** Active recall testing, Spaced repetition learning, Personalized mastery map, Identify over 60 fallacies, Real-world scenario analysis

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| All Access (1 Month) | $1.99 | per month |
| All Access (1 Year) | $11.99 | per year |


## Frequently asked questions

### Is Interactive Photosynthesis free?

Interactive Photosynthesis costs $1.99, with no in-app purchases.

### Is Logical Fallacy Memory free?

Logical Fallacy Memory is free to download, with in-app purchases available.

### Do Interactive Photosynthesis or Logical Fallacy Memory have ads?

Neither Interactive Photosynthesis nor Logical Fallacy Memory shows ads.

### Which is updated more often, Interactive Photosynthesis or Logical Fallacy Memory?

Interactive Photosynthesis ships an update every 25 months, and Logical Fallacy Memory every 2 weeks. Most recently, Interactive Photosynthesis was updated on November 7, 2026 and Logical Fallacy Memory on November 4, 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.*