# Mamori vs Sea Depth

The clearest difference is in-app purchases: Mamori at none against Sea Depth's 10. Mamori also leads on iOS requirement (13.0 vs 15.0). Sea Depth's advantage is update cadence (every 5 days vs every 5 months). On price, ads and device support there is nothing between them.

Both are free to download. Sea Depth sells 10 in-app purchases, starting at $99.99 per year. Mamori asks for nothing beyond the download.

Mamori ships an update every 5 months, Sea Depth every 5 days. The most recent releases landed on October 3, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Mamori | Sea Depth |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.2 (16 ratings)](https://appshunter.io/ios/app/sea-depth/id6747972372/reviews)** |
| Number of ratings | — | **16** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 5 days** |
| Monetization | — | Free with in-app purchases |
| Size | 128 MB | 106 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Trackimo LLC](https://appshunter.io/developer/796838009) | [Seadepth Charts, LLC](https://appshunter.io/developer/1823642107) |

## What reviewers say

### Mamori

[App page](https://appshunter.io/ios/app/mamori/id1567247692)

**Features:** macOS Compatibility

**In-app purchases:** none


### 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 Mamori free?

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

### Is Sea Depth free?

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

### Do Mamori or Sea Depth have ads?

Neither Mamori nor Sea Depth shows ads.

### Which is updated more often, Mamori or Sea Depth?

Mamori ships an update every 5 months, and Sea Depth every 5 days. Most recently, Mamori was updated on October 3, 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.*