# FCD vs GateRelay

The clearest difference is in-app purchases: FCD at none against GateRelay's 1. GateRelay's advantage is update cadence (every 9 days vs every 7 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. GateRelay sells 1 one-off in-app purchase. FCD asks for nothing beyond the download.

FCD ships an update every 7 months, GateRelay every 9 days. The most recent releases landed on September 8, 2026 and September 14, 2026 respectively.

## The numbers

| Metric | FCD | GateRelay |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/fcd-tr1-adapter-application/id1438537309/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 9 days** |
| Monetization | Free | — |
| Size | 2 MB | 36 MB |
| Requires iOS | **14.4** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Ross Morrison](https://appshunter.io/developer/1438537308) | [George Alexandrou](https://appshunter.io/developer/1875566334) |

## What reviewers say

### FCD

[App page](https://appshunter.io/ios/app/fcd-tr1-adapter-application/id1438537309)

This application calibrates engine gauges for turboprop aircraft using an iPad. It connects via Bluetooth to a specialized adapter plugged into the back of the gauges, allowing full control of calibration parameters and download of flight log data.

**Highlights:** iPad-based calibration, Bluetooth connectivity, Control calibration parameters, Download flight log data, Supports TR1 engine gauges

**Features:** macOS Compatibility

**In-app purchases:** none


### GateRelay

[App page](https://appshunter.io/ios/app/gaterelay-gsm-gate-control/id6760940464)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| GateRelay Pro | $9.99 | one-time |


## Frequently asked questions

### Is FCD free?

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

### Is GateRelay free?

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

### Do FCD or GateRelay have ads?

Neither FCD nor GateRelay shows ads.

### Which is updated more often, FCD or GateRelay?

FCD ships an update every 7 months, and GateRelay every 9 days. Most recently, FCD was updated on September 8, 2026 and GateRelay on September 14, 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.*