# RT vs Cortex Onboard

The clearest difference is review sentiment: Cortex Onboard at 56% against RT's 0%. Cortex Onboard also leads on rating (3.8 vs 3.0) and in-app purchases (none vs 5). RT's advantage is chart position (#197 vs unranked). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. RT sells 5 one-off in-app purchases. Cortex Onboard asks for nothing beyond the download.

Cortex Onboard holds the better App Store score, 3.8 against 3.0. Both are backed by a comparable volume of ratings — 8 and 12 respectively. Written reviews point the same way: 0% of RT's written reviews are positive against 56% of Cortex Onboard's.

RT ships an update monthly, Cortex Onboard every 2 months. The most recent releases landed on September 23, 2026 and June 7, 2026 respectively.

## The numbers

| Metric | RT | Cortex Onboard |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.0 (8 ratings)](https://appshunter.io/ios/app/rt-nav/id586307815/reviews) | **[3.8 (12 ratings)](https://appshunter.io/ios/app/cortex-onboard/id1483406085/reviews)** |
| Number of ratings | 8 | **12** |
| Positive reviews | 0.0% of reviews | **55.6% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Monthly** | Every 2 months |
| Monetization | Free with in-app purchases | **Free** |
| Best chart rank | **#197** | — |
| Size | 13 MB | 376 MB |
| Requires iOS | 26.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Hilton's Fishing Charts, L.L.C.](https://appshunter.io/developer/586307818) | [Garmin New Zealand Ltd](https://appshunter.io/developer/557485484) |

## What reviewers say

### RT

[App page](https://appshunter.io/ios/app/rt-nav/id586307815)

**Currently charting:** #197 Top Grossing · Navigation (US App Store)

Navigate using real-time oceanographic data like sea surface temperatures and currents on your mobile device. Create and edit waypoints, zoom maps, and track your GPS location for point-to-point navigation. Access dynamic maps even without cell service.

**Highlights:** Real-time oceanographic imagery, Waypoint creation and editing, Map zooming, Point-to-point navigation, Real-time GPS tracking, Offline navigation capabilities

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

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Day Subscription | $29.99 | one-time |
| 1 Week Subscription | $49.99 | one-time |
| 1 Month Subscription | $99.99 | one-time |
| 1 Year Subscription | $199.99 | one-time |
| One Year International | $199.99 | one-time |


### Cortex Onboard

[App page](https://appshunter.io/ios/app/cortex-onboard/id1483406085)

This app allows you to configure and update your marine electronics from your mobile device. Monitor vessel data, receive alerts, and manage features like Anchor Watch from anywhere on board.

**Highlights:** Configure and update Cortex devices, View AIS information and alerts, Manage Anchor Watch, Monitor vessel sensors, Connect NMEA 2000 instruments

**In-app purchases:** none


## Frequently asked questions

### Is RT free?

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

### Is Cortex Onboard free?

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

### Which has better reviews, RT or Cortex Onboard?

Cortex Onboard is rated higher. RT averages 3.0 out of 5 from 8 ratings, while Cortex Onboard averages 3.8 from 12 ratings.

### Do RT or Cortex Onboard have ads?

Neither RT nor Cortex Onboard shows ads.

### Which is updated more often, RT or Cortex Onboard?

RT ships an update monthly, and Cortex Onboard every 2 months. Most recently, RT was updated on September 23, 2026 and Cortex Onboard on June 7, 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.*