# LogTen Pilot Logbook vs GTP API Gravity Calculator2

The clearest difference is review sentiment: GTP API Gravity Calculator2 at 100% against LogTen Pilot Logbook's 38%. GTP API Gravity Calculator2 also leads on in-app purchases (none vs 11) and iOS requirement (12.0 vs 15.0). LogTen Pilot Logbook's advantage is price (Free vs $9.99) and rating (4.7 vs 4.0). On ads and chart position there is nothing between them.

LogTen Pilot Logbook is free to download; GTP API Gravity Calculator2 costs $9.99 up front. LogTen Pilot Logbook sells 10 in-app purchases, starting at $9.99 per month. GTP API Gravity Calculator2 asks for nothing beyond the download.

LogTen Pilot Logbook holds the better App Store score, 4.7 against 4.0. That said, the two scores are not equally well evidenced: LogTen Pilot Logbook has 10K ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 38% of LogTen Pilot Logbook's written reviews are positive against 100% of GTP API Gravity Calculator2's, so the app with the better star average is not the one people write more warmly about.

LogTen Pilot Logbook ships an update fortnightly, GTP API Gravity Calculator2 every 2 months. The most recent releases landed on September 25, 2026 and September 8, 2026 respectively.

## The numbers

| Metric | LogTen Pilot Logbook | GTP API Gravity Calculator2 |
| --- | --- | --- |
| Price | **Free** | $9.99 |
| Rating | **[4.7 (10K ratings)](https://appshunter.io/ios/app/logten-pilot-logbook/id837274884/reviews)** | [4.0 (1 ratings)](https://appshunter.io/ios/app/gtp-api-gravity-calculator2/id6742924006/reviews) |
| Number of ratings | **10K** | 1 |
| Positive reviews | 37.5% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | **Free with in-app purchases** | Paid |
| Best chart rank | **#100** | #193 |
| Size | 225 MB | 9 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | **iPhone, iPad, iPod, Apple Watch** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Coradine Aviation Systems](https://appshunter.io/developer/286222901) | [Gammon Technical Products](https://appshunter.io/developer/1163782116) |

## What reviewers say

### LogTen Pilot Logbook

[App page](https://appshunter.io/ios/app/logten-pilot-logbook/id837274884)

**Currently charting:** #100 Top Grossing · Utilities (US App Store)

This digital flight logbook helps pilots track flight hours, currency, and certificates. It offers automated data entry, powerful analytics, and career advancement tools.  Free for the first 50 hours of flight time.

**Highlights:** Lightning-fast data entry, Automated and customizable logging, Syncs across all devices, Automated and manual backups, Key flight analytics, Smart Group technology for tracking, Career matching and job search

**Features:** Apple Watch app

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Founder Basic | $9.99 | per month |
| Basic | $9.99 | per month |
| Pro | $14.99 | per month |
| Founder Pro | $14.99 | per month |
| Enterprise Basic | $69.99 | per year |
| Founder Basic | $74.99 | per year |
| Basic | $79.99 | per year |
| Enterprise Pro | $99.99 | per year |
| Founder Pro | $104.99 | per year |
| Pro | $129.99 | per year |

**What reviewers like**

- 🚀 Keeps getting better
- 👍 Great customer support
- 🚀 Friendly and intuitive
- 👍 Wonderful support for any issue
- 👍 Excellent app for logging flights

**What reviewers complain about**

- 🐛 Crashes and sync issues
- 🐛 Random discrepancies between devices
- 🐛 Lost all data after update
- 🐛 Importing flight data is horrible
- 🐛 Missing data after years of use

**Reported bugs**

- Entire logbook data wiped out after update
- Sync issues causing data loss
- Backup and restore functionality not reliable
- Logbook entries disappearing or getting corrupted

**Requested features**

- Ability to log simulator and instrument flying
- Direct import of airline schedules
- Unlimited crew labels
- Ability to annotate route of flight
- More customization options for logbook layout


### GTP API Gravity Calculator2

[App page](https://appshunter.io/ios/app/gtp-api-gravity-calculator2/id6742924006)

**Currently charting:** #193 Top Paid · Utilities (US App Store)

This application calculates the corrected API gravity at 60°F for jet, gasoline, and diesel fuels. It also determines the total weight of the fuel. It's a digital replacement for physical slide calculators.

**Highlights:** Corrected API gravity calculation, Total fuel weight calculation, Supports jet, gasoline, and diesel fuels, Digital version of slide calculators, Developed in 2025

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

**In-app purchases:** none


## Frequently asked questions

### Is LogTen Pilot Logbook free?

LogTen Pilot Logbook is free to download, with in-app purchases available.

### Is GTP API Gravity Calculator2 free?

GTP API Gravity Calculator2 costs $9.99, with no in-app purchases.

### Which has better reviews, LogTen Pilot Logbook or GTP API Gravity Calculator2?

LogTen Pilot Logbook is rated higher. LogTen Pilot Logbook averages 4.7 out of 5 from 10K ratings, while GTP API Gravity Calculator2 averages 4.0 from 1 ratings.

### Do LogTen Pilot Logbook or GTP API Gravity Calculator2 have ads?

Neither LogTen Pilot Logbook nor GTP API Gravity Calculator2 shows ads.

### Which is updated more often, LogTen Pilot Logbook or GTP API Gravity Calculator2?

LogTen Pilot Logbook ships an update fortnightly, and GTP API Gravity Calculator2 every 2 months. Most recently, LogTen Pilot Logbook was updated on September 25, 2026 and GTP API Gravity Calculator2 on September 8, 2026.

### Which is more popular, LogTen Pilot Logbook or GTP API Gravity Calculator2?

LogTen Pilot Logbook currently peaks at #100 in the App Store charts, and GTP API Gravity Calculator2 at #193. Chart position reflects recent download velocity rather than total install base.

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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.*