# myHarkness Calculator vs Diamond ECL

The clearest difference is price: myHarkness Calculator at Free against Diamond ECL's $1.99. myHarkness Calculator also leads on iOS requirement (11.0 vs 17). On update cadence, ads, in-app purchases and device support there is nothing between them.

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

myHarkness Calculator ships an update every 3 months, Diamond ECL every 2 months. The most recent releases landed on September 20, 2026 and September 9, 2026 respectively.

## The numbers

| Metric | myHarkness Calculator | Diamond ECL |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Size | 79 MB | 1 MB |
| Requires iOS | **11.0** | 17 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Harkness Screens Ltd](https://appshunter.io/developer/987523118) | [Gadir Mamedov](https://appshunter.io/developer/1628780398) |

## What reviewers say

### myHarkness Calculator

[App page](https://appshunter.io/ios/app/myharkness-calculator/id792736941)

**In-app purchases:** none


### Diamond ECL

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

**In-app purchases:** none


## Frequently asked questions

### Is myHarkness Calculator free?

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

### Is Diamond ECL free?

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

### Do myHarkness Calculator or Diamond ECL have ads?

Neither myHarkness Calculator nor Diamond ECL shows ads.

### Which is updated more often, myHarkness Calculator or Diamond ECL?

myHarkness Calculator ships an update every 3 months, and Diamond ECL every 2 months. Most recently, myHarkness Calculator was updated on September 20, 2026 and Diamond ECL on September 9, 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.*