# 20以内加减法口算 vs 数感星球

The clearest difference is in-app purchases: 20以内加减法口算 at none against 数感星球's 24. 20以内加减法口算 also leads on iOS requirement (9.0 vs 13.0). 数感星球's advantage is update cadence (fortnightly vs every 23 months) and rating (4.5 vs 4.3). On price, review sentiment, ratings volume and ads there is nothing between them.

Both are free to download. 数感星球 sells 23 one-off in-app purchases. 20以内加减法口算 asks for nothing beyond the download.

数感星球 holds the better App Store score, 4.5 against 4.3. Both are backed by a comparable volume of ratings — 56 and 71 respectively. Written reviews complicate that: 100% of 20以内加减法口算's written reviews are positive against 92% of 数感星球's, so the app with the better star average is not the one people write more warmly about.

20以内加减法口算 ships an update every 23 months, 数感星球 fortnightly. The most recent releases landed on October 14, 2026 and October 23, 2026 respectively.

## The numbers

| Metric | 20以内加减法口算 | 数感星球 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.3 (56 ratings)](https://appshunter.io/ios/app/20/id1087409662/reviews) | **[4.5 (71 ratings)](https://appshunter.io/ios/app/id1481755599/reviews)** |
| Number of ratings | 56 | **71** |
| Positive reviews | **100.0% of reviews** | 92.2% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 23 months | **Fortnightly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 42 MB | 463 MB |
| Requires iOS | **9.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [华 周](https://appshunter.io/developer/569428357) | [Ahaaa Education Technology Co., Ltd.](https://appshunter.io/developer/1470347128) |

## What reviewers say

### 20以内加减法口算

[App page](https://appshunter.io/ios/app/20/id1087409662)

This app helps children aged 3-7 develop essential mental math skills with addition and subtraction problems up to 20. It uses engaging game-based learning with varying difficulty levels and includes practice and timed test modes.

**Highlights:** Addition and subtraction up to 20, Mixed operation practice, Game-based learning, Multiple difficulty levels, Practice mode with hints, Timed test mode, Voice prompts

**Features:** macOS Compatibility

**In-app purchases:** none


### 数感星球

[App page](https://appshunter.io/ios/app/id1481755599)

This app uses AI and gamified lessons to help children aged 3-10 develop number sense and improve their calculation skills. It offers a structured 16-level training system and visual learning experiences to make math concepts easier to understand and practice.

**Highlights:** AI-powered personalized training, Gamified calculation exercises, 16-level progressive learning system, Visual and interactive math concepts, Data-driven learning reports, CPA teaching methodology

**Features:** Vision Pro support

**In-app purchases (23)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 方向位置 - 专题训练 | $9.99 | one-time |
| 观察与推理专项训练包 | $9.99 | one-time |
| 6个月会员 | $39.99 | one-time |
| 续费专享优惠 | $39.99 | one-time |
| VIP年卡会员-续费专属套餐 | $39.99 | one-time |
| 数感星球-续费专属 | $39.99 | one-time |
| 数感星球-一年会员赠送120天优惠价328赠货币达人 | $49.99 | one-time |
| 数感星球-一年会员赠送180天优惠价328赠数游记+货币达人 | $49.99 | one-time |
| 数感星球-一年会员赠送120天+数游记+货币达人优惠价328 | $49.99 | one-time |
| 数感星球-1年会员 | $49.99 | one-time |
| 数感星球-1年会员（买1年送3个月） | $49.99 | one-time |
| 数感星球-1年会员（ 续费用户专享） | $49.99 | one-time |
| 数感星球-1年会员（加赠120天） | $49.99 | one-time |
| 活动特惠-买1年赠90天 | $49.99 | one-time |
| 老用户专享（赠300天） | $49.99 | one-time |
| 1年会员折扣价 | $49.99 | one-time |
| 数感星球-1年会员（买1年送2个月） | $49.99 | one-time |
| 活动特惠(加赠300天） | $49.99 | one-time |
| 活动特惠-买1年赠180天 | $49.99 | one-time |
| 活动优惠 | $49.99 | one-time |
| 双十一活动（买1年送1年） | $59.99 | one-time |
| 数感星球-1年会员（买1年送1年） | $59.99 | one-time |
| 数感星球-1年会员（送1年+3个专项训练课程） | $59.99 | one-time |


## Frequently asked questions

### Is 20以内加减法口算 free?

20以内加减法口算 is free to download, with no in-app purchases.

### Is 数感星球 free?

数感星球 is free to download, with in-app purchases available.

### Which has better reviews, 20以内加减法口算 or 数感星球?

数感星球 is rated higher. 20以内加减法口算 averages 4.3 out of 5 from 56 ratings, while 数感星球 averages 4.5 from 71 ratings.

### Do 20以内加减法口算 or 数感星球 have ads?

Neither 20以内加减法口算 nor 数感星球 shows ads.

### Which is updated more often, 20以内加减法口算 or 数感星球?

20以内加减法口算 ships an update every 23 months, and 数感星球 fortnightly. Most recently, 20以内加减法口算 was updated on October 14, 2026 and 数感星球 on October 23, 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.*