# GTP API Gravity Calculator2 vs PixelTrace

The clearest difference is price: PixelTrace at Free against GTP API Gravity Calculator2's $9.99. PixelTrace also leads on rating (5.0 vs 4.0). GTP API Gravity Calculator2's advantage is update cadence (every 2 months vs every 5 months) and iOS requirement (12.0 vs 15.1). On ratings volume, ads, in-app purchases and device support there is nothing between them.

PixelTrace is free to download; GTP API Gravity Calculator2 costs $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

PixelTrace holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

GTP API Gravity Calculator2 ships an update every 2 months, PixelTrace every 5 months. The most recent releases landed on October 24, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | GTP API Gravity Calculator2 | PixelTrace |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| Rating | [4.0 (1 ratings)](https://appshunter.io/ios/app/gtp-api-gravity-calculator2/id6742924006/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/pixeltrace/id6761668956/reviews)** |
| Number of ratings | 1 | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 5 months |
| Monetization | Paid | **Free** |
| Size | 9 MB | 53 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Gammon Technical Products](https://appshunter.io/developer/1163782116) | [Chroma Lightshows LLC](https://appshunter.io/developer/1886583035) |

## What reviewers say

### GTP API Gravity Calculator2

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

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


### PixelTrace

[App page](https://appshunter.io/ios/app/pixeltrace/id6761668956)

This app helps users create and reference wiring diagrams for pixel lighting projects. Browse vendor catalogs, view interactive diagrams, and export them for easy printing and sharing.

**Highlights:** Browse and search prop catalogs, Interactive wiring diagrams, Printable PDF export, Favorites for quick access, Syncs with xLights vendor library

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

**In-app purchases:** none


## Frequently asked questions

### Is GTP API Gravity Calculator2 free?

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

### Is PixelTrace free?

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

### Which has better reviews, GTP API Gravity Calculator2 or PixelTrace?

PixelTrace is rated higher. GTP API Gravity Calculator2 averages 4.0 out of 5 from 1 ratings, while PixelTrace averages 5.0 from 1 ratings.

### Do GTP API Gravity Calculator2 or PixelTrace have ads?

Neither GTP API Gravity Calculator2 nor PixelTrace shows ads.

### Which is updated more often, GTP API Gravity Calculator2 or PixelTrace?

GTP API Gravity Calculator2 ships an update every 2 months, and PixelTrace every 5 months. Most recently, GTP API Gravity Calculator2 was updated on October 24, 2026 and PixelTrace on October 18, 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.*