# Brain Reactor vs Sum Fun

The clearest difference is in-app purchases: Sum Fun at none against Brain Reactor's 1. Sum Fun also leads on review sentiment (100% vs 71%) and update cadence (every 2 weeks vs every 5 weeks). Brain Reactor's advantage is ads (none vs shown). On price, ratings volume and device support there is nothing between them.

Both are free to download. Brain Reactor sells 1 one-off in-app purchase. Sum Fun asks for nothing beyond the download.

Sum Fun holds the better App Store score, 4.9 against 4.7. Both are backed by a comparable volume of ratings — 20 and 33 respectively. Written reviews point the same way: 71% of Brain Reactor's written reviews are positive against 100% of Sum Fun's.

Brain Reactor ships an update every 5 weeks, Sum Fun every 2 weeks. Both last shipped on November 13, 2026.

## The numbers

| Metric | Brain Reactor | Sum Fun |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (20 ratings)](https://appshunter.io/ios/app/brain-reactor/id386182342/reviews) | **[4.9 (33 ratings)](https://appshunter.io/ios/app/sum-fun/id817544892/reviews)** |
| Number of ratings | 20 | **33** |
| Positive reviews | 71.4% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Every 5 weeks | **Every 2 weeks** |
| Monetization | Free with in-app purchases | **Ad-supported** |
| Size | 8 MB | 186 MB |
| Requires iOS | 17.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 4+ |
| Developer | [Buzly Labs Ltd.](https://appshunter.io/developer/380854584) | [Wondrous Minds Company Limited](https://appshunter.io/developer/817544895) |

## What reviewers say

### Brain Reactor

[App page](https://appshunter.io/ios/app/brain-reactor/id386182342)

A multiplayer party game for 1-4 players on a single device. Test your reflexes and quick thinking with a variety of mini-games. Perfect for gatherings, it offers local play with no internet connection required.

**Highlights:** 1-4 player local multiplayer, Variety of quick mini-games, Single device gameplay, Customizable match settings, Light/Dark/Auto appearance modes, Responsive layouts for different devices

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Brain Reactor Full Game | $2.99 | one-time |


### Sum Fun

[App page](https://appshunter.io/ios/app/sum-fun/id817544892)

A unique number puzzle game that combines logic, numbers, and strategy. Enjoy endlessly replayable puzzles with creative board shapes and a brain-boosting gameplay experience. Play at your own pace with no time limits and challenge friends.

**Highlights:** Unique number puzzle gameplay, Variety of creative board shapes, Brain-boosting mental workout, No time limits for relaxed play, Challenge friends offline, Easy to play, fun to master

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

**In-app purchases:** none


## Frequently asked questions

### Is Brain Reactor free?

Brain Reactor is free to download, with in-app purchases available.

### Is Sum Fun free?

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

### Which has better reviews, Brain Reactor or Sum Fun?

Sum Fun is rated higher. Brain Reactor averages 4.7 out of 5 from 20 ratings, while Sum Fun averages 4.9 from 33 ratings.

### Do Brain Reactor or Sum Fun have ads?

Sum Fun shows ads; Brain Reactor does not.

### Which is updated more often, Brain Reactor or Sum Fun?

Brain Reactor ships an update every 5 weeks, and Sum Fun every 2 weeks. Most recently, Brain Reactor was updated on November 13, 2026 and Sum Fun on November 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.*