# Obkio vs Rocket Calculator

The clearest difference is in-app purchases: Obkio at none against Rocket Calculator's 1. Obkio also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.0). Rocket Calculator's advantage is update cadence (weekly vs every 6 weeks). On price and ads there is nothing between them.

Both are free to download. Rocket Calculator sells 1 one-off in-app purchase. Obkio asks for nothing beyond the download.

Obkio ships an update every 6 weeks, Rocket Calculator weekly. The most recent releases landed on October 26, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Obkio | Rocket Calculator |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Weekly** |
| Size | 61 MB | 1 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Obkio inc.](https://appshunter.io/developer/1351109853) | [毅 王](https://appshunter.io/developer/6774631380) |

## What reviewers say

### Obkio

[App page](https://appshunter.io/ios/app/obkio/id1351924056)

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

**In-app purchases:** none


### Rocket Calculator

[App page](https://appshunter.io/ios/app/rocket-calculator-apogeefield/id6778329350)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ApogeeField Unlock | $4.99 | one-time |


## Frequently asked questions

### Is Obkio free?

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

### Is Rocket Calculator free?

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

### Do Obkio or Rocket Calculator have ads?

Neither Obkio nor Rocket Calculator shows ads.

### Which is updated more often, Obkio or Rocket Calculator?

Obkio ships an update every 6 weeks, and Rocket Calculator weekly. Most recently, Obkio was updated on October 26, 2026 and Rocket Calculator on October 28, 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.*