# protostar vs K3學中文 (寫字認字)

The clearest difference is price: protostar at Free against K3學中文 (寫字認字)'s $7.99. protostar also leads on update cadence (every 3 weeks vs every 9 months). K3學中文 (寫字認字)'s advantage is in-app purchases (none vs 1) and ads (none vs shown). On iOS requirement there is nothing between them.

protostar is free to download; K3學中文 (寫字認字) costs $7.99 up front. protostar sells 1 one-off in-app purchase. K3學中文 (寫字認字) asks for nothing beyond the download.

protostar ships an update every 3 weeks, K3學中文 (寫字認字) every 9 months. The most recent releases landed on October 4, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | protostar | K3學中文 (寫字認字) |
| --- | --- | --- |
| Price | **Free** | $7.99 |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/protostar/id1504821938/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 3 weeks** | Every 9 months |
| Monetization | Free with in-app purchases | — |
| Size | 155 MB | 362 MB |
| Requires iOS | 10 | **9.0** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Longzhe Education Technology (Shanghai) Co., Ltd.](https://appshunter.io/developer/1504821937) | [Yiu Ying Ching](https://appshunter.io/developer/1667170345) |

## What reviewers say

### protostar

[App page](https://appshunter.io/ios/app/protostar/id1504821938)

This educational app is designed for students aged 7-12, offering a platform for watching learning videos and playing interactive games. It is exclusively for users of the protostar education company and is available on iPad.

**Highlights:** Learning videos, Educational games, Preview content, Review content, Designed for ages 7-12

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Protostar English Course | $299.99 | one-time |


### K3學中文 (寫字認字)

[App page](https://appshunter.io/ios/app/k3/id1669891510)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is protostar free?

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

### Is K3學中文 (寫字認字) free?

K3學中文 (寫字認字) costs $7.99, with no in-app purchases.

### Do protostar or K3學中文 (寫字認字) have ads?

protostar shows ads; K3學中文 (寫字認字) does not.

### Which is updated more often, protostar or K3學中文 (寫字認字)?

protostar ships an update every 3 weeks, and K3學中文 (寫字認字) every 9 months. Most recently, protostar was updated on October 4, 2026 and K3學中文 (寫字認字) on October 3, 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.*