# Sight Calc vs VesselFinder

The clearest difference is review sentiment: Sight Calc at 82% against VesselFinder's 28%. Sight Calc also leads on rating (5.0 vs 4.1) and ads (none vs shown). VesselFinder's advantage is price (Free vs $1.99) and update cadence (fortnightly vs every 11 months). On in-app purchases, device support and iOS requirement there is nothing between them.

VesselFinder is free to download; Sight Calc costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Sight Calc holds the better App Store score, 5.0 against 4.1. That said, the two scores are not equally well evidenced: VesselFinder has 232 ratings behind it against 7, so its average is the more settled of the two. Written reviews point the same way: 82% of Sight Calc's written reviews are positive against 28% of VesselFinder's.

Sight Calc ships an update every 11 months, VesselFinder fortnightly. The most recent releases landed on September 10, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | Sight Calc | VesselFinder |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | **[5.0 (7 ratings)](https://appshunter.io/ios/app/sight-calc/id497809138/reviews)** | [4.1 (232 ratings)](https://appshunter.io/ios/app/vesselfinder/id918080862/reviews) |
| Number of ratings | 7 | **232** |
| Positive reviews | **82.4% of reviews** | 27.9% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 11 months | **Fortnightly** |
| Monetization | Paid | **Free with in-app purchases** |
| Best chart rank | — | **#190** |
| Size | 1 MB | 47 MB |
| Requires iOS | 16.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [NUVOCOM INCORPORATED](https://appshunter.io/developer/497809141) | [AstraPaging Ltd.](https://appshunter.io/developer/438160792) |

## What reviewers say

### Sight Calc

[App page](https://appshunter.io/ios/app/sight-calc/id497809138)

This app is a specialized calculator for sight reductions using the Law of Cosines method. It's designed for students learning celestial navigation and requires manual input of LHA, declination, and approximate latitude.

**Highlights:** Law of Cosines sight reduction, Manual LHA, declination, and latitude input, Input as degrees/minutes or decimal degrees, Continuous computation of Hc, Z, and Zn, Supports North/South latitude and declination conventions, Clear and clear entry functions, Convert minutes to decimal degrees

**Features:** macOS Compatibility

**In-app purchases:** none


### VesselFinder

[App page](https://appshunter.io/ios/app/vesselfinder/id918080862)

**Currently charting:** #190 Top Free · Navigation (US App Store)

Track ships and monitor maritime traffic globally in real-time. Access detailed vessel information, movement history, and predicted routes. Ideal for maritime professionals and enthusiasts alike.

**Highlights:** Real-time vessel tracking, Vessel movement history, Predicted routes and ETAs, Comprehensive vessel particulars, Port call details, My Fleet for favorite vessels, Weather overlays

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

**In-app purchases:** none

**What reviewers like**

- 👍 Simple and intuitive user interface
- 💰 Free version provides basic functionality
- 🗺️ Clear map display with sea blue and land green
- 📊 Comprehensive vessel information available
- ⚓ Good for casual ship tracking and hobbyists

**What reviewers complain about**

- ⏱️ Severely outdated vessel position data (days old)
- 🐛 App freezes on startup/splash screen frequently
- 💸 Misleading free version with limited functionality
- 🔄 Inconsistent and unreliable data updates
- ❌ Search functionality requires paid version

**Reported bugs**

- App freezes on splash screen and won't load
- Crashes when attempting to zoom on map
- Black screen display on certain devices
- App won't open or opens after long delays
- Crashes on iOS 11 and newer versions

**Requested features**

- Real-time GPS tracking instead of delayed AIS data
- Distance measurement tool restoration
- German language support
- Destination and departure information display
- Ability to remove ads without expensive pro version


## Frequently asked questions

### Is Sight Calc free?

Sight Calc costs $1.99, with no in-app purchases.

### Is VesselFinder free?

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

### Which has better reviews, Sight Calc or VesselFinder?

Sight Calc is rated higher. Sight Calc averages 5.0 out of 5 from 7 ratings, while VesselFinder averages 4.1 from 232 ratings.

### Do Sight Calc or VesselFinder have ads?

VesselFinder shows ads; Sight Calc does not.

### Which is updated more often, Sight Calc or VesselFinder?

Sight Calc ships an update every 11 months, and VesselFinder fortnightly. Most recently, Sight Calc was updated on September 10, 2026 and VesselFinder on September 23, 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.*