# Calculate Comfort vs Eterna App

The clearest difference is in-app purchases: Eterna App at none against Calculate Comfort's 1. Eterna App also leads on ads (none vs shown). Calculate Comfort's advantage is update cadence (every 4 months vs every 8 months). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Calculate Comfort sells 1 one-off in-app purchase. Eterna App asks for nothing beyond the download.

Calculate Comfort ships an update every 4 months, Eterna App every 8 months. The most recent releases landed on October 23, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Calculate Comfort | Eterna App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.9 (35 ratings)](https://appshunter.io/ios/app/calculate-comfort/id605648449/reviews)** | — |
| Number of ratings | **35** | — |
| Positive reviews | 75.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 4 months** | Every 8 months |
| Monetization | Free with in-app purchases | — |
| Size | 13 MB | 29 MB |
| Requires iOS | 16.0 | **15.1** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [JUN KANAYAMA](https://appshunter.io/developer/605648452) | [ETERNA APP SPV LIMITED](https://appshunter.io/developer/1797083215) |

## What reviewers say

### Calculate Comfort

[App page](https://appshunter.io/ios/app/calculate-comfort/id605648449)

This app analyzes atmospheric conditions by calculating various air properties like relative humidity, dew point, and enthalpy. It provides visual indicators for comfort levels and allows for easy adjustment of input values using a dial. Advanced features include weather data fetching and unit conversions.

**Highlights:** Calculates RH, Dew Point, Wet-Bulb Temp, Enthalpy, and more, Visual comfort indicators with color and emoji, Adjustable atmospheric pressure input, Switchable between Discomfort Index (DI) and WBGT, Automatic weather data fetching, Unit conversion between SI and US units (Pro), Export calculation results as text (Pro)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Version | $7.99 | one-time |


### Eterna App

[App page](https://appshunter.io/ios/app/eterna-app/id6742149129)

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

**In-app purchases:** none


## Frequently asked questions

### Is Calculate Comfort free?

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

### Is Eterna App free?

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

### Do Calculate Comfort or Eterna App have ads?

Calculate Comfort shows ads; Eterna App does not.

### Which is updated more often, Calculate Comfort or Eterna App?

Calculate Comfort ships an update every 4 months, and Eterna App every 8 months. Most recently, Calculate Comfort was updated on October 23, 2026 and Eterna App on October 28, 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.*