# OrbitCalc vs Feynman WTF

The clearest difference is device support: Feynman WTF at 3 against OrbitCalc's 1. Feynman WTF also leads on iOS requirement (15.1 vs 18.0). On price, ads and in-app purchases there is nothing between them.

Both are free to download. OrbitCalc sells 1 one-off in-app purchase and Feynman WTF sells 2 in-app purchases, starting at $10.00 per month. Whichever you choose, the download price is not the number that matters.

## The numbers

| Metric | OrbitCalc | Feynman WTF |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/orbitcalc/id6743425109/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | — | Weekly |
| Monetization | Free | — |
| Size | 11 MB | 37 MB |
| Requires iOS | 18.0 | **15.1** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Bian Dhoan Kwik](https://appshunter.io/developer/1793925532) | [Vrushal Kapadnis](https://appshunter.io/developer/1830846117) |

## What reviewers say

### OrbitCalc

[App page](https://appshunter.io/ios/app/orbitcalc/id6743425109)

This tool helps space enthusiasts, engineers, and researchers precisely calculate satellite orbits. It allows users to determine orbital parameters from vector data or vice versa with accurate results. Save and manage your calculations, and customize measurement units for a personalized experience.

**Highlights:** Orbital calculations from parameters or vectors, Save and revisit previous calculations, History page for managing saved work, Customizable measurement units

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| OrbitCalc Pro | $0.99 | one-time |


### Feynman WTF

[App page](https://appshunter.io/ios/app/feynman-wtf/id6749510148)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $10.00 | per month |
| Pro Yearly | $99.99 | per year |


## Frequently asked questions

### Is OrbitCalc free?

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

### Is Feynman WTF free?

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

### Do OrbitCalc or Feynman WTF have ads?

Neither OrbitCalc nor Feynman WTF shows ads.

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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.*