# Merwins EPV Calculator vs Epic Authenticator

The clearest difference is rating: Merwins EPV Calculator at 5.0 against Epic Authenticator's 2.5. Merwins EPV Calculator also leads on update cadence (every 5 months vs every 16 months). Epic Authenticator's advantage is ratings volume (39 vs 8) and iOS requirement (16.0 vs 26.6). 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.

Merwins EPV Calculator holds the better App Store score, 5.0 against 2.5. Both are backed by a comparable volume of ratings — 8 and 39 respectively.

Merwins EPV Calculator ships an update every 5 months, Epic Authenticator every 16 months. The most recent releases landed on October 13, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Merwins EPV Calculator | Epic Authenticator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (8 ratings)](https://appshunter.io/ios/app/merwins-epv-calculator/id1062647500/reviews)** | [2.5 (39 ratings)](https://appshunter.io/ios/app/epic-authenticator/id1437572933/reviews) |
| Number of ratings | 8 | **39** |
| Positive reviews | — | 26.7% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 5 months** | Every 16 months |
| Monetization | Free | Free |
| Size | 25 MB | 5 MB |
| Requires iOS | 26.6 | **16.0** |
| Devices | iPhone, iPad | **iPhone, iPad, Apple Watch** |
| Age rating | 17+ | 4+ |
| Developer | [Harperfection Corporation](https://appshunter.io/developer/406488551) | [Epic](https://appshunter.io/developer/348308666) |

## What reviewers say

### Merwins EPV Calculator

[App page](https://appshunter.io/ios/app/merwins-epv-calculator/id1062647500)

This utility app calculates the volume of a spherical cap using Merwin's equation based on width, height, and thickness measurements. It plots results on a normative curve and can calculate placenta weight percentile.

**Highlights:** Calculates spherical cap volume, Uses Merwin's equation, Plots results on normative curves, Calculates placenta weight percentile, Supports landscape mode for plots, Easy data entry and sharing

**Features:** Vision Pro support

**In-app purchases:** none


### Epic Authenticator

[App page](https://appshunter.io/ios/app/epic-authenticator/id1437572933)

This app enhances security for your electronic health record system by providing two-factor authentication. It sends notifications to your phone for login verification or offers temporary passcodes for access.

**Highlights:** Two-factor authentication, Login notifications, Temporary passcodes, Enhanced credential security, Epic EHR system integration

**Features:** Apple Watch app

**In-app purchases:** none


## Frequently asked questions

### Is Merwins EPV Calculator free?

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

### Is Epic Authenticator free?

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

### Which has better reviews, Merwins EPV Calculator or Epic Authenticator?

Merwins EPV Calculator is rated higher. Merwins EPV Calculator averages 5.0 out of 5 from 8 ratings, while Epic Authenticator averages 2.5 from 39 ratings.

### Do Merwins EPV Calculator or Epic Authenticator have ads?

Neither Merwins EPV Calculator nor Epic Authenticator shows ads.

### Which is updated more often, Merwins EPV Calculator or Epic Authenticator?

Merwins EPV Calculator ships an update every 5 months, and Epic Authenticator every 16 months. Most recently, Merwins EPV Calculator was updated on October 13, 2026 and Epic Authenticator on October 14, 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.*