# eFace Auth vs HydroCalc Basic

The clearest difference is in-app purchases: eFace Auth at none against HydroCalc Basic's 1. eFace Auth also leads on iOS requirement (13.0 vs 15.1). On price, ads and device support there is nothing between them.

Both are free to download. HydroCalc Basic sells 1 one-off in-app purchase. eFace Auth asks for nothing beyond the download.

## The numbers

| Metric | eFace Auth | HydroCalc Basic |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | — | Every 11 days |
| Size | 28 MB | 35 MB |
| Requires iOS | **13.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [SkimProt Ltd.](https://appshunter.io/developer/1507981256) | [Transparent Blue Water LLC](https://appshunter.io/developer/1847968351) |

## What reviewers say

### eFace Auth

[App page](https://appshunter.io/ios/app/eface-auth/id1532238542)

**Features:** macOS Compatibility

**In-app purchases:** none


### 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 |


## Frequently asked questions

### Is eFace Auth free?

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

### Is HydroCalc Basic free?

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

### Do eFace Auth or HydroCalc Basic have ads?

Neither eFace Auth nor HydroCalc Basic shows ads.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*