# ReactionFlash vs MARVLS

The clearest difference is iOS requirement: ReactionFlash at 14.0 against MARVLS's 18.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Both ship on a similar rhythm, roughly every 4 months. The most recent releases landed on October 23, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | ReactionFlash | MARVLS |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (42 ratings)](https://appshunter.io/ios/app/reactionflash/id432080813/reviews)** | — |
| Number of ratings | **42** | — |
| Positive reviews | 80.6% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | Every 4 months |
| Monetization | Free | — |
| Size | 37 MB | 242 MB |
| Requires iOS | **14.0** | 18.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 9+ |
| Developer | [Elsevier Limited](https://appshunter.io/developer/1437273934) | [Michele McColgan](https://appshunter.io/developer/1532617986) |

## What reviewers say

### ReactionFlash

[App page](https://appshunter.io/ios/app/reactionflash/id432080813)

This app serves as a comprehensive flashcard-style learning tool for named chemical reactions. It provides detailed information on reaction mechanisms and examples from scientific literature, with a quiz mode to test user knowledge.

**Highlights:** Learn named chemical reactions, Understand reaction mechanisms, View literature examples, Quiz mode for knowledge testing, Flashcard interface

**Features:** macOS Compatibility

**In-app purchases:** none


### MARVLS

[App page](https://appshunter.io/ios/app/marvls-physics-i-mechanics/id6475370470)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ReactionFlash free?

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

### Is MARVLS free?

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

### Do ReactionFlash or MARVLS have ads?

Neither ReactionFlash nor MARVLS shows ads.

### Which is updated more often, ReactionFlash or MARVLS?

ReactionFlash ships an update every 4 months, and MARVLS every 4 months. Most recently, ReactionFlash was updated on October 23, 2026 and MARVLS on October 3, 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.*