# Propeller Calc vs ECPin Pro

The clearest difference is review sentiment: Propeller Calc at 100% against ECPin Pro's 14%. ECPin Pro's advantage is update cadence (every 5 weeks vs every 21 months) and iOS requirement (11.0 vs 17.0). On price, ads, in-app purchases and monetization model there is nothing between them.

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

Propeller Calc ships an update every 21 months, ECPin Pro every 5 weeks. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Propeller Calc | ECPin Pro |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (1 ratings)](https://appshunter.io/ios/app/propeller-calc/id478119478/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | **100.0% of reviews** | 14.3% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 21 months | **Every 5 weeks** |
| Monetization | Free | Free |
| Size | 3 MB | 119 MB |
| Requires iOS | 17.0 | **11.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Frode Rørvik](https://appshunter.io/developer/478119481) | [MANFORD DEVELOPMENT LIMITED](https://appshunter.io/developer/1440169840) |

## 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


### ECPin Pro

[App page](https://appshunter.io/ios/app/ecpin-pro/id1499962987)

This app works with a wireless thermometer to help you achieve perfect cooking results. Monitor real-time temperature and get notified when your food is ready, all from your phone.

**Highlights:** Real-time temperature monitoring, Customizable cooking presets, Wireless connectivity, Notifications for doneness, Supports multiple devices, Water-resistant thermometer

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Propeller Calc free?

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

### Is ECPin Pro free?

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

### Do Propeller Calc or ECPin Pro have ads?

Neither Propeller Calc nor ECPin Pro shows ads.

### Which is updated more often, Propeller Calc or ECPin Pro?

Propeller Calc ships an update every 21 months, and ECPin Pro every 5 weeks. Most recently, Propeller Calc was updated on November 1, 2026 and ECPin Pro on November 3, 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.*