# On My Marks vs Sea Depth

The clearest difference is rating: On My Marks at 5.0 against Sea Depth's 4.2. Sea Depth's advantage is update cadence (every 5 days vs every 2 weeks) and ratings volume (16 vs 2). On price, review sentiment, ads and in-app purchases there is nothing between them.

Both are free to download. On My Marks sells 1 in-app purchase, starting at $49.99 per year and Sea Depth sells 10 in-app purchases, starting at $99.99 per year. Whichever you choose, the download price is not the number that matters.

On My Marks holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: Sea Depth has 16 ratings behind it against 2, so its average is the more settled of the two. Written reviews split almost evenly too, at 100% and 100% positive.

On My Marks ships an update every 2 weeks, Sea Depth every 5 days. The most recent releases landed on October 17, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | On My Marks | Sea Depth |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/on-my-marks/id6737274150/reviews)** | [4.2 (16 ratings)](https://appshunter.io/ios/app/sea-depth/id6747972372/reviews) |
| Number of ratings | 2 | **16** |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Every 5 days** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 61 MB | 106 MB |
| Requires iOS | 17.6 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [On My Marks, LLC](https://appshunter.io/developer/1775694456) | [Seadepth Charts, LLC](https://appshunter.io/developer/1823642107) |

## What reviewers say

### On My Marks

[App page](https://appshunter.io/ios/app/on-my-marks/id6737274150)

Organize and manage your GPS waypoints from various devices and software. Easily import, edit, merge, and export your marks to declutter and streamline your navigation data for fishing, boating, diving, and outdoor exploration.

**Highlights:** Import GPS waypoints, Edit waypoint data, Merge duplicate waypoints, Export waypoint data, Supports Garmin Active Captain, Supports Simrad, C-Map, Lowrance

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Yearly Subscription | $49.99 | per year |


### Sea Depth

[App page](https://appshunter.io/ios/app/sea-depth/id6747972372)

Visualize detailed underwater terrain with high-resolution bathymetric charts. Gain deeper insights into seafloor structure, contours, and terrain for offshore activities. Includes optional data overlays and waypoint management for enhanced situational awareness.

**Highlights:** High-resolution shaded-relief bathymetry, Detailed depth contours with intelligent labeling, Optional data overlays (pipelines, bottom composition), GPX waypoint import/export, Drift Test tool, Offline chart access

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Charts Access | $99.99 | per year |
| Western GOA 50% | $150.00 | one-time |
| Eastern GOA 30% | $209.99 | one-time |
| Cental GOA 20% | $239.99 | one-time |
| Eastern GOA 20% | $239.99 | one-time |
| Cental GOA | $300.00 | one-time |
| Western GOA | $300.00 | one-time |
| Eastern GOA | $300.00 | one-time |
| Florida-West Coast | $300.00 | one-time |
| South Florida/Northern Bahamas | $300.00 | one-time |


## Frequently asked questions

### Is On My Marks free?

On My Marks is free to download, with in-app purchases available.

### Is Sea Depth free?

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

### Which has better reviews, On My Marks or Sea Depth?

On My Marks is rated higher. On My Marks averages 5.0 out of 5 from 2 ratings, while Sea Depth averages 4.2 from 16 ratings.

### Do On My Marks or Sea Depth have ads?

Neither On My Marks nor Sea Depth shows ads.

### Which is updated more often, On My Marks or Sea Depth?

On My Marks ships an update every 2 weeks, and Sea Depth every 5 days. Most recently, On My Marks was updated on October 17, 2026 and Sea Depth 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.*