# TruAirspeed vs Diamond ECL

The clearest difference is price: TruAirspeed at Free against Diamond ECL's $1.99. TruAirspeed also leads on iOS requirement (15.6 vs 17). Diamond ECL's advantage is update cadence (every 2 months vs every 24 months). On ads, in-app purchases and device support there is nothing between them.

TruAirspeed is free to download; Diamond ECL costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

TruAirspeed ships an update every 24 months, Diamond ECL every 2 months. The most recent releases landed on October 2, 2026 and September 27, 2026 respectively.

## The numbers

| Metric | TruAirspeed | Diamond ECL |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[4.1 (8 ratings)](https://appshunter.io/ios/app/truairspeed/id855269892/reviews)** | — |
| Number of ratings | **8** | — |
| Positive reviews | 71.4% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 24 months | **Every 2 months** |
| Monetization | Free | — |
| Size | 8 MB | 1 MB |
| Requires iOS | **15.6** | 17 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [James Petty](https://appshunter.io/developer/603661046) | [Gadir Mamedov](https://appshunter.io/developer/1628780398) |

## What reviewers say

### TruAirspeed

[App page](https://appshunter.io/ios/app/truairspeed/id855269892)

This utility calculates true airspeed, pressure altitude, density altitude, and Mach number. It accounts for compressibility effects and offers unit choices and keypad styles. Users can also input a correction factor for their airspeed indicator.

**Highlights:** True airspeed calculation, Pressure and density altitude calculation, Mach number calculation, Compressibility effects accounted for, Choice of input/result units, Calculator or telephone keypad options, Airspeed indicator correction factor

**Features:** macOS Compatibility

**In-app purchases:** none


### Diamond ECL

[App page](https://appshunter.io/ios/app/diamond-ecl/id1628780396)

**In-app purchases:** none


## Frequently asked questions

### Is TruAirspeed free?

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

### Is Diamond ECL free?

Diamond ECL costs $1.99, with no in-app purchases.

### Do TruAirspeed or Diamond ECL have ads?

Neither TruAirspeed nor Diamond ECL shows ads.

### Which is updated more often, TruAirspeed or Diamond ECL?

TruAirspeed ships an update every 24 months, and Diamond ECL every 2 months. Most recently, TruAirspeed was updated on October 2, 2026 and Diamond ECL on September 27, 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.*