# Kalkulilo (Calculator) vs HVAC Psychrometric Plus

The clearest difference is rating: Kalkulilo (Calculator) at 4.5 against HVAC Psychrometric Plus's 3.0. Kalkulilo (Calculator) also leads on price ($2.99 vs $6.99) and update cadence (every 2 months vs every 6 months). HVAC Psychrometric Plus's advantage is chart position (#182 vs unranked). On review sentiment, ads, in-app purchases and device support there is nothing between them.

Kalkulilo (Calculator) costs $2.99 and HVAC Psychrometric Plus $6.99 up front. Kalkulilo (Calculator) sells 1 one-off in-app purchase and HVAC Psychrometric Plus sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Kalkulilo (Calculator) holds the better App Store score, 4.5 against 3.0. That said, the two scores are not equally well evidenced: Kalkulilo (Calculator) has 29 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 76% of Kalkulilo (Calculator)'s written reviews are positive against 73% of HVAC Psychrometric Plus's.

Kalkulilo (Calculator) ships an update every 2 months, HVAC Psychrometric Plus every 6 months. Both last shipped on November 10, 2026.

## The numbers

| Metric | Kalkulilo (Calculator) | HVAC Psychrometric Plus |
| --- | --- | --- |
| Price | **$2.99** | $6.99 |
| Rating | **[4.5 (29 ratings)](https://appshunter.io/ios/app/kalkulilo-calculator/id286091993/reviews)** | [3.0 (2 ratings)](https://appshunter.io/ios/app/hvac-psychrometric-plus/id348669031/reviews) |
| Number of ratings | **29** | 2 |
| Positive reviews | **75.8% of reviews** | 72.7% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 6 months |
| Monetization | **Free with in-app purchases** | Paid |
| Best chart rank | — | **#182** |
| Size | 3 MB | 1 MB |
| Requires iOS | **16.0** | 17.0 |
| Devices | **iPhone, iPad, Apple Watch** | iPhone, iPad |
| Age rating | 4+ | +4 |
| Developer | [Alexander Clauss](https://appshunter.io/developer/286091996) | [Carmel Software Corporation](https://appshunter.io/developer/317970398) |

## What reviewers say

### Kalkulilo (Calculator)

[App page](https://appshunter.io/ios/app/kalkulilo-calculator/id286091993)

This app offers a versatile calculator with multiple modes, including scientific, bitwise, statistical, trigonometric, base conversion, and time calculations. It features a simple mode with large buttons and customizable interface. Widgets for notification center and Apple Watch are also included.

**Highlights:** Scientific calculator functions, Bit/integer mode with logical operations, Statistical calculations, Base/radix conversion (2-36), Time value calculations, Customizable interface, Apple Watch app and widget

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.99 | one-time |

**What reviewers like**

- 🚀 Excellent, powerful calculator
- 👍 Variety of modes and number systems
- 👍 Intuitive and easy to use
- 👍 Highly functional for engineers, programmers, and students
- 👍 Replaces physical scientific calculators

**What reviewers complain about**

- 🐛 Stopped working after OS update
- 💰 Ads introduced after being paid app
- 👎 Buttons too small, hard to press
- 🔍 Confusing color scheme and UI

**Reported bugs**

- Number doesn't transfer correctly when switching between modes
- Negative exponents not displayed correctly in engineering notation
- Loses calculation history when changing modes

**Requested features**

- Add calculus, linear algebra, and probability functions
- Implement a 'repeated equals' function
- Add a backspace/delete button
- Allow customizing color scheme
- Improve Apple Watch integration


### HVAC Psychrometric Plus

[App page](https://appshunter.io/ios/app/hvac-psychrometric-plus/id348669031)

**Currently charting:** #182 Top Paid · Productivity (US App Store)

Perform single-state and mixed-air psychrometric calculations quickly and easily. Select input parameters and view updated results on a single screen. Supports 23 input combinations and offers email/spreadsheet export.

**Highlights:** Single-state psychrometric calculations, Mixed-air psychrometric calculations, 23 input parameter combinations, Real-time result updates, Universal app for iPhone and iPad, Email and spreadsheet export

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| HVAC Equipment Locator | $9.99 | one-time |


## Frequently asked questions

### Is Kalkulilo (Calculator) free?

Kalkulilo (Calculator) costs $2.99, and also offers in-app purchases.

### Is HVAC Psychrometric Plus free?

HVAC Psychrometric Plus costs $6.99, and also offers in-app purchases.

### Which has better reviews, Kalkulilo (Calculator) or HVAC Psychrometric Plus?

Kalkulilo (Calculator) is rated higher. Kalkulilo (Calculator) averages 4.5 out of 5 from 29 ratings, while HVAC Psychrometric Plus averages 3.0 from 2 ratings.

### Do Kalkulilo (Calculator) or HVAC Psychrometric Plus have ads?

Neither Kalkulilo (Calculator) nor HVAC Psychrometric Plus shows ads.

### Which is updated more often, Kalkulilo (Calculator) or HVAC Psychrometric Plus?

Kalkulilo (Calculator) ships an update every 2 months, and HVAC Psychrometric Plus every 6 months. Most recently, Kalkulilo (Calculator) was updated on November 10, 2026 and HVAC Psychrometric Plus on November 10, 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.*