# Shin Reaction Mechanism vs Backside Attack

The clearest difference is in-app purchases: Backside Attack at none against Shin Reaction Mechanism's 1. Backside Attack also leads on ratings volume (74 vs 1) and device support (4 vs 2). Shin Reaction Mechanism's advantage is update cadence (monthly vs every 8 months). On price, rating, review sentiment and ads there is nothing between them.

Both are free to download. Shin Reaction Mechanism sells 1 one-off in-app purchase. Backside Attack asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for Shin Reaction Mechanism against 4.9 for Backside Attack. That said, the two scores are not equally well evidenced: Backside Attack has 74 ratings behind it against 1, so its average is the more settled of the two. Written reviews are what separate them: 89% of Shin Reaction Mechanism's written reviews are positive against 95% of Backside Attack's.

Shin Reaction Mechanism ships an update monthly, Backside Attack every 8 months. The most recent releases landed on October 23, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | Shin Reaction Mechanism | Backside Attack |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/shin-reaction-mechanism/id674401547/reviews)** | [4.9 (74 ratings)](https://appshunter.io/ios/app/backside-attack/id1278956096/reviews) |
| Number of ratings | 1 | **74** |
| Positive reviews | 89.5% of reviews | **95.5% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Monthly** | Every 8 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 174 MB | 178 MB |
| Requires iOS | 17.0 | **9.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [junpei ono](https://appshunter.io/developer/656630939) | [Element26, Inc.](https://appshunter.io/developer/973213639) |

## What reviewers say

### Shin Reaction Mechanism

[App page](https://appshunter.io/ios/app/shin-reaction-mechanism/id674401547)

This application provides a quick search for hundreds of organic chemistry reaction mechanisms. It is designed to be an essential tool for students learning the subject.

**Highlights:** Hundreds of reaction mechanisms, Quick search functionality, Essential for organic chemistry learning, Designed for students

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 詳細画面解放 | $2.99 | one-time |


### Backside Attack

[App page](https://appshunter.io/ios/app/backside-attack/id1278956096)

This educational game helps students grasp fundamental organic chemistry concepts, specifically focusing on the SN2 reaction. It explores key variables like leaving group ability, nucleophilicity, steric factors, and solvent effects to build a strong foundation in chemistry.

**Highlights:** Learn SN2 reaction mechanics, Explore leaving group ability, Understand nucleophilicity, Analyze steric factors, Study solvent effects, Earn points with Check Yourself +50, Unlock Chem Yourself feature

**In-app purchases:** none


## Frequently asked questions

### Is Shin Reaction Mechanism free?

Shin Reaction Mechanism is free to download, with in-app purchases available.

### Is Backside Attack free?

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

### Which has better reviews, Shin Reaction Mechanism or Backside Attack?

Shin Reaction Mechanism is rated higher. Shin Reaction Mechanism averages 5.0 out of 5 from 1 ratings, while Backside Attack averages 4.9 from 74 ratings.

### Do Shin Reaction Mechanism or Backside Attack have ads?

Neither Shin Reaction Mechanism nor Backside Attack shows ads.

### Which is updated more often, Shin Reaction Mechanism or Backside Attack?

Shin Reaction Mechanism ships an update monthly, and Backside Attack every 8 months. Most recently, Shin Reaction Mechanism was updated on October 23, 2026 and Backside Attack on October 22, 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.*