# AC Calculator vs Smart Firelog

The clearest difference is in-app purchases: Smart Firelog at none against AC Calculator's 2. Smart Firelog also leads on update cadence (daily vs every 4 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. AC Calculator sells 2 one-off in-app purchases. Smart Firelog asks for nothing beyond the download.

AC Calculator ships an update every 4 months, Smart Firelog daily. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | AC Calculator | Smart Firelog |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (20 ratings)](https://appshunter.io/ios/app/ac-calculator-hvac-sizing/id1537174761/reviews)** | — |
| Number of ratings | **20** | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 months | **Daily** |
| Monetization | Free with in-app purchases | — |
| Size | 9 MB | 6 MB |
| Requires iOS | 18.6 | **17.0** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Melchisedec Martinez Rodriguez](https://appshunter.io/developer/1534398511) | [monitored247](https://appshunter.io/developer/1749633983) |

## What reviewers say

### AC Calculator

[App page](https://appshunter.io/ios/app/ac-calculator-hvac-sizing/id1537174761)

This utility app simplifies HVAC sizing by calculating BTU/h capacity and recommending equipment. It offers unit conversions, price estimates, and energy consumption comparisons. Advanced features can be unlocked via in-app purchases.

**Highlights:** Calculate BTU/h capacity, Recommend equipment types, Convert BTU, kW, Kcal, Tons, Check price estimates, Compare inverter vs. conventional

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock View details | $4.99 | one-time |
| Unlock Advanced mode | $9.99 | one-time |


### Smart Firelog

[App page](https://appshunter.io/ios/app/smart-firelog/id6761857541)

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

**In-app purchases:** none


## Frequently asked questions

### Is AC Calculator free?

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

### Is Smart Firelog free?

Smart Firelog is free to download, with no in-app purchases.

### Do AC Calculator or Smart Firelog have ads?

Neither AC Calculator nor Smart Firelog shows ads.

### Which is updated more often, AC Calculator or Smart Firelog?

AC Calculator ships an update every 4 months, and Smart Firelog daily. Most recently, AC Calculator was updated on November 3, 2026 and Smart Firelog on October 31, 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.*