# Addition Algorithm vs Reading Fluency

The clearest difference is in-app purchases: Addition Algorithm at none against Reading Fluency's 4. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Reading Fluency sells 4 in-app purchases, starting at $2.99 per 7 days. Addition Algorithm asks for nothing beyond the download.

Addition Algorithm ships an update every 6 days, Reading Fluency every 5 days. The most recent releases landed on October 1, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | Addition Algorithm | Reading Fluency |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 days | **Every 5 days** |
| Size | 56 MB | 28 MB |
| Requires iOS | **16.0** | 17.6 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [JASON A RIGBY](https://appshunter.io/developer/1811566397) | [Mehmet Demir](https://appshunter.io/developer/1522952577) |

## What reviewers say

### Addition Algorithm

[App page](https://appshunter.io/ios/app/addition-algorithm/id6760708208)

**Features:** macOS Compatibility

**In-app purchases:** none


### Reading Fluency

[App page](https://appshunter.io/ios/app/reading-fluency-kidsread/id6770613013)

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| KidsRead Weekly | $2.99 | per 7 days |
| KidsRead Monthly | $6.99 | per month |
| KidsRead Annual | $24.99 | per year |
| KidsRead Lifetime Premium | $34.99 | one-time |


## Frequently asked questions

### Is Addition Algorithm free?

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

### Is Reading Fluency free?

Reading Fluency is free to download, with in-app purchases available.

### Do Addition Algorithm or Reading Fluency have ads?

Neither Addition Algorithm nor Reading Fluency shows ads.

### Which is updated more often, Addition Algorithm or Reading Fluency?

Addition Algorithm ships an update every 6 days, and Reading Fluency every 5 days. Most recently, Addition Algorithm was updated on October 1, 2026 and Reading Fluency on October 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.*