# Propeller Calc vs GuavaDrop

The clearest difference is rating: GuavaDrop at 5.0 against Propeller Calc's 3.0. GuavaDrop also leads on update cadence (every 6 weeks vs every 21 months) and iOS requirement (15.0 vs 17.0). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

GuavaDrop holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

Propeller Calc ships an update every 21 months, GuavaDrop every 6 weeks. The most recent releases landed on September 26, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | Propeller Calc | GuavaDrop |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.0 (1 ratings)](https://appshunter.io/ios/app/propeller-calc/id478119478/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/guavadrop/id1619055284/reviews)** |
| Number of ratings | 1 | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 21 months | **Every 6 weeks** |
| Monetization | Free | Free |
| Size | 3 MB | 2 MB |
| Requires iOS | 17.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Frode Rørvik](https://appshunter.io/developer/478119481) | [Azukipan IT Solutions LLC](https://appshunter.io/developer/1604498724) |

## What reviewers say

### Propeller Calc

[App page](https://appshunter.io/ios/app/propeller-calc/id478119478)

This utility calculates propeller performance metrics like pitch, gear ratio, RPM, slip, and speed. Input any four values, and the app computes the fifth, helping users understand the relationship between propeller design and boat performance.

**Highlights:** Calculate pitch, gear ratio, RPM, slip, and speed, Enter any four variables to find the fifth, Understand propeller slip and its impact, Supports iPhone and iPad, Free to use

**Features:** macOS Compatibility

**In-app purchases:** none


### GuavaDrop

[App page](https://appshunter.io/ios/app/guavadrop/id1619055284)

Easily scan, create, and manage QR codes. View QR code content as text messages for convenient access. Designed for both personal and business productivity.

**Highlights:** Scan QR codes, Create QR codes, Save QR codes, View QR code content as text, Personal productivity, Business productivity

**In-app purchases:** none


## Frequently asked questions

### Is Propeller Calc free?

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

### Is GuavaDrop free?

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

### Which has better reviews, Propeller Calc or GuavaDrop?

GuavaDrop is rated higher. Propeller Calc averages 3.0 out of 5 from 1 ratings, while GuavaDrop averages 5.0 from 1 ratings.

### Do Propeller Calc or GuavaDrop have ads?

Neither Propeller Calc nor GuavaDrop shows ads.

### Which is updated more often, Propeller Calc or GuavaDrop?

Propeller Calc ships an update every 21 months, and GuavaDrop every 6 weeks. Most recently, Propeller Calc was updated on September 26, 2026 and GuavaDrop on October 16, 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.*