# HydroCalc Basic vs Aeshna

The clearest difference is update cadence: HydroCalc Basic at every 11 days against Aeshna's every 6 weeks. HydroCalc Basic also leads on iOS requirement (15.1 vs 18.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. HydroCalc Basic sells 1 one-off in-app purchase and Aeshna sells 10 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

HydroCalc Basic ships an update every 11 days, Aeshna every 6 weeks. The most recent releases landed on September 8, 2026 and September 20, 2026 respectively.

## The numbers

| Metric | HydroCalc Basic | Aeshna |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 11 days** | Every 6 weeks |
| Size | 35 MB | 57 MB |
| Requires iOS | **15.1** | 18.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Age rating | 4+ | 4+ |
| Developer | [Transparent Blue Water LLC](https://appshunter.io/developer/1847968351) | [Shenzhen Seize Times E-Commerce Co., Ltd.](https://appshunter.io/developer/368397197) |

## What reviewers say

### HydroCalc Basic

[App page](https://appshunter.io/ios/app/hydrocalc-basic/id6752577110)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium - Flow Units & Ad-Free | $1.99 | one-time |


### Aeshna

[App page](https://appshunter.io/ios/app/aeshna/id6758001353)

**Features:** Vision Pro support

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Viewra Models (Monthly) | $4.99 | per month |
| Viewra BIMs (Monthly) | $4.99 | per month |
| Viewra Complete (Monthly) | $6.99 | per month |
| Viewra Models (Yearly) | $34.99 | per year |
| Viewra BIMs (Monthly) | $34.99 | per year |
| Viewra Complete (Yearly) | $49.99 | per year |
| Viewra Drawings (Lifetime) | $39.99 | one-time |
| Viewra Models (Lifetime) | $69.99 | one-time |
| Viewra BIMs (Lifetime) | $69.99 | one-time |
| Viewra Complete (Lifetime) | $99.99 | one-time |


## Frequently asked questions

### Is HydroCalc Basic free?

HydroCalc Basic is free to download, with in-app purchases available.

### Is Aeshna free?

Aeshna is free to download, with in-app purchases available.

### Do HydroCalc Basic or Aeshna have ads?

Neither HydroCalc Basic nor Aeshna shows ads.

### Which is updated more often, HydroCalc Basic or Aeshna?

HydroCalc Basic ships an update every 11 days, and Aeshna every 6 weeks. Most recently, HydroCalc Basic was updated on September 8, 2026 and Aeshna on September 20, 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.*