# 易数 vs 投影与视图3D教具

The clearest difference is in-app purchases: 易数 at none against 投影与视图3D教具's 4. 易数 also leads on iOS requirement (9.0 vs 15.0). 投影与视图3D教具's advantage is device support (6 vs 2). On price and ads there is nothing between them.

Both are free to download. 投影与视图3D教具 sells 4 in-app purchases, starting at $0.99 per month. 易数 asks for nothing beyond the download.

## The numbers

| Metric | 易数 | 投影与视图3D教具 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | — | Every 4 days |
| Size | 56 MB | 8 MB |
| Requires iOS | **9.0** | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod, Mac, Apple Watch, Vision Pro** |
| Age rating | 4+ | 4+ |
| Developer | [Henan Ben Network Technology Co. Ltd.](https://appshunter.io/developer/1251318448) | [天添 叶](https://appshunter.io/developer/6799125945) |

## What reviewers say

### 易数

[App page](https://appshunter.io/ios/app/id1615529904)

**Features:** macOS Compatibility

**In-app purchases:** none


### 投影与视图3D教具

[App page](https://appshunter.io/ios/app/3d/id6804217452)

**Features:** Apple Watch app

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Membership | $0.99 | per month |
| Weekly Membership | $0.99 | per 7 days |
| Yearly Membership | $2.99 | per year |
| Lifetime Membership | $3.99 | one-time |


## Frequently asked questions

### Is 易数 free?

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

### Is 投影与视图3D教具 free?

投影与视图3D教具 is free to download, with in-app purchases available.

### Do 易数 or 投影与视图3D教具 have ads?

Neither 易数 nor 投影与视图3D教具 shows ads.

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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.*