# 連立方程式 vs Pi Sequence

The clearest difference is in-app purchases: 連立方程式 at none against Pi Sequence's 1. Pi Sequence's advantage is device support. On price and iOS requirement there is nothing between them.

Both are free to download. Pi Sequence sells 1 one-off in-app purchase. 連立方程式 asks for nothing beyond the download.

## The numbers

| Metric | 連立方程式 | Pi Sequence |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | — | No |
| Update frequency | — | Every 3 months |
| Size | 6 MB | 29 MB |
| Requires iOS | **16.4** | 17.0 |
| Devices | — | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Risako Asai](https://appshunter.io/developer/1671273580) | [晓灵 潘](https://appshunter.io/developer/6781908128) |

## What reviewers say

### 連立方程式

[App page](https://appshunter.io/ios/app/id6483928960)

**In-app purchases:** none


### Pi Sequence

[App page](https://appshunter.io/ios/app/pi-sequence-memorize-pi/id6783736734)

**Features:** Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Pro | $3.99 | one-time |


## Frequently asked questions

### Is 連立方程式 free?

連立方程式 is free to download, with no in-app purchases.

### Is Pi Sequence free?

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

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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.*