# 高校数学の解法 vs Def Init

The clearest difference is in-app purchases: Def Init at none against 高校数学の解法's 2. Def Init also leads on ads (none vs shown). 高校数学の解法's advantage is update cadence (every 4 days vs every 3 weeks). On price, device support and iOS requirement there is nothing between them.

Both are free to download. 高校数学の解法 sells 2 one-off in-app purchases. Def Init asks for nothing beyond the download.

高校数学の解法 ships an update every 4 days, Def Init every 3 weeks. The most recent releases landed on October 10, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | 高校数学の解法 | Def Init |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 4 days** | Every 3 weeks |
| Size | 152 MB | 33 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Shogo Shibuya](https://appshunter.io/developer/1671795647) | [DeMiA](https://appshunter.io/developer/1541788198) |

## What reviewers say

### 高校数学の解法

[App page](https://appshunter.io/ios/app/id6445906314)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 広告の非表示 | $2.99 | one-time |
| Premium（買い切り） | $14.99 | one-time |


### Def Init

[App page](https://appshunter.io/ios/app/def-init/id6746444302)

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

**In-app purchases:** none


## Frequently asked questions

### Is 高校数学の解法 free?

高校数学の解法 is free to download, with in-app purchases available.

### Is Def Init free?

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

### Do 高校数学の解法 or Def Init have ads?

高校数学の解法 shows ads; Def Init does not.

### Which is updated more often, 高校数学の解法 or Def Init?

高校数学の解法 ships an update every 4 days, and Def Init every 3 weeks. Most recently, 高校数学の解法 was updated on October 10, 2026 and Def Init on October 2, 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.*