# 進数・補数変換 vs Java SE 21 Developer

The clearest difference is in-app purchases: 進数・補数変換 at none against Java SE 21 Developer's 1. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Java SE 21 Developer sells 1 one-off in-app purchase. 進数・補数変換 asks for nothing beyond the download.

Both ship on a similar rhythm, roughly weekly. The most recent releases landed on October 19, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | 進数・補数変換 | Java SE 21 Developer |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Weekly | Weekly |
| Size | 3 MB | 203 MB |
| Requires iOS | 16.0 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Manato Abe](https://appshunter.io/developer/1766487879) | [CHOI SEONGMIN](https://appshunter.io/developer/6772332527) |

## What reviewers say

### 進数・補数変換

[App page](https://appshunter.io/ios/app/id6702007723)

**Features:** macOS Compatibility

**In-app purchases:** none


### Java SE 21 Developer

[App page](https://appshunter.io/ios/app/java-se-21-developer/id6785110070)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime Access | $4.99 | one-time |


## Frequently asked questions

### Is 進数・補数変換 free?

進数・補数変換 is free to download, with no in-app purchases.

### Is Java SE 21 Developer free?

Java SE 21 Developer is free to download, with in-app purchases available.

### Do 進数・補数変換 or Java SE 21 Developer have ads?

Neither 進数・補数変換 nor Java SE 21 Developer shows ads.

### Which is updated more often, 進数・補数変換 or Java SE 21 Developer?

進数・補数変換 ships an update weekly, and Java SE 21 Developer weekly. Most recently, 進数・補数変換 was updated on October 19, 2026 and Java SE 21 Developer on October 24, 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.*