# ReadFlow vs SigmaQuest

The clearest difference is ads: ReadFlow at none against SigmaQuest's shown. ReadFlow also leads on iOS requirement (15.0 vs 18.0). On price, in-app purchases and device support there is nothing between them.

Both are free to download. ReadFlow sells 2 in-app purchases, starting at $2.99 per month and SigmaQuest sells 10 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

## The numbers

| Metric | ReadFlow | SigmaQuest |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 4 months | — |
| Size | 95 MB | 7 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Hasan Karli](https://appshunter.io/developer/1700265388) | [NICOLAS JORGE PETRIDES](https://appshunter.io/developer/6798856218) |

## What reviewers say

### ReadFlow

[App page](https://appshunter.io/ios/app/readflow-speed-reading/id6770712256)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| premium | $2.99 | per month |
| premium | $29.99 | per year |


### SigmaQuest

[App page](https://appshunter.io/ios/app/sigmaquest-learn-statistics/id6805579459)

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Gauss | $1.99 | one-time |
| Professor Sigma | $1.99 | one-time |
| Nutty | $1.99 | one-time |
| Bayes | $1.99 | one-time |
| Asymp | $1.99 | one-time |
| Vegas | $1.99 | one-time |
| Outlier | $1.99 | one-time |
| Alpha | $1.99 | one-time |
| The Central Limit | $1.99 | one-time |
| Unlock All Buddies | $9.99 | one-time |


## Frequently asked questions

### Is ReadFlow free?

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

### Is SigmaQuest free?

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

### Do ReadFlow or SigmaQuest have ads?

SigmaQuest shows ads; ReadFlow does not.

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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.*