# RC Speed Calculator Pro vs CastleLink2

The clearest difference is ratings volume: RC Speed Calculator Pro at 23 against CastleLink2's 2. RC Speed Calculator Pro also leads on update cadence (fortnightly vs monthly) and iOS requirement (17.0 vs 26.0). On price, rating, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 4.9 for RC Speed Calculator Pro against 5.0 for CastleLink2. That said, the two scores are not equally well evidenced: RC Speed Calculator Pro has 23 ratings behind it against 2, so its average is the more settled of the two.

RC Speed Calculator Pro ships an update fortnightly, CastleLink2 monthly. The most recent releases landed on September 23, 2026 and September 8, 2026 respectively.

## The numbers

| Metric | RC Speed Calculator Pro | CastleLink2 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.9 (23 ratings)](https://appshunter.io/ios/app/rc-speed-calculator-pro/id6445860835/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/castlelink2/id6743709203/reviews)** |
| Number of ratings | **23** | 2 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Monthly |
| Monetization | Free | Free |
| Size | 160 MB | 35 MB |
| Requires iOS | **17.0** | 26.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Degree3, Inc.](https://appshunter.io/developer/1497876563) | [Castle Creations Inc](https://appshunter.io/developer/1377811229) |

## What reviewers say

### RC Speed Calculator Pro

[App page](https://appshunter.io/ios/app/rc-speed-calculator-pro/id6445860835)

Estimate your RC car's top speed by inputting details about its gearing, motor, and batteries. Record your estimates and actual speeds to compare different setups.

**Highlights:** Estimate RC car top speed, Input gearing, motor, and battery info, Record speed estimates, Log actual top speeds, Compare different car setups, Pre-filled car data

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

**In-app purchases:** none


### CastleLink2

[App page](https://appshunter.io/ios/app/castlelink2/id6743709203)

Connect to Castle Creations ESCs and BECs via Bluetooth to adjust settings, update firmware, and view data logs. Compatible with a wide range of ESCs and BECs, supporting both B-Link hardware versions.

**Highlights:** Connect to Castle Creations ESCs/BECs, Adjust settings, Update firmware, View data logs, Supports B-Link adapters, Wide ESC/BEC compatibility

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

**In-app purchases:** none


## Frequently asked questions

### Is RC Speed Calculator Pro free?

RC Speed Calculator Pro is free to download, with no in-app purchases.

### Is CastleLink2 free?

CastleLink2 is free to download, with no in-app purchases.

### Which has better reviews, RC Speed Calculator Pro or CastleLink2?

CastleLink2 is rated higher. RC Speed Calculator Pro averages 4.9 out of 5 from 23 ratings, while CastleLink2 averages 5.0 from 2 ratings.

### Do RC Speed Calculator Pro or CastleLink2 have ads?

Neither RC Speed Calculator Pro nor CastleLink2 shows ads.

### Which is updated more often, RC Speed Calculator Pro or CastleLink2?

RC Speed Calculator Pro ships an update fortnightly, and CastleLink2 monthly. Most recently, RC Speed Calculator Pro was updated on September 23, 2026 and CastleLink2 on September 8, 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.*