# A4Calc vs Fire Door Pro

The clearest difference is price: Fire Door Pro at Free against A4Calc's $4.99. A4Calc's advantage is iOS requirement (12.0 vs 15.1). On update cadence, ads, in-app purchases and device support there is nothing between them.

Fire Door Pro is free to download; A4Calc costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

A4Calc ships an update every 8 months, Fire Door Pro every 7 months. The most recent releases landed on September 30, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | A4Calc | Fire Door Pro |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | — | **[3.0 (2 ratings)](https://appshunter.io/ios/app/fire-door-pro/id1590592330/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 8 months | **Every 7 months** |
| Monetization | — | Free |
| Size | 2 MB | 41 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Farren Domenici](https://appshunter.io/developer/583666476) | [Debra Bragg](https://appshunter.io/developer/1590592332) |

## What reviewers say

### A4Calc

[App page](https://appshunter.io/ios/app/a4calc/id734140182)

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

**In-app purchases:** none


### Fire Door Pro

[App page](https://appshunter.io/ios/app/fire-door-pro/id1590592330)

Streamline fire door inspections with this app. It guides you through the 13-point NFPA 80 inspection process, allowing you to collect data, upload photos, and generate instant reports. Save time and money on your fire door assessments.

**Highlights:** 13-point NFPA 80 inspection guide, Electronic and hard copy report generation, Photo upload for doors and deficiencies, Door-specific notes and code correction details, Systematic inspection process with safeguards

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

**In-app purchases:** none


## Frequently asked questions

### Is A4Calc free?

A4Calc costs $4.99, with no in-app purchases.

### Is Fire Door Pro free?

Fire Door Pro is free to download, with no in-app purchases.

### Do A4Calc or Fire Door Pro have ads?

Neither A4Calc nor Fire Door Pro shows ads.

### Which is updated more often, A4Calc or Fire Door Pro?

A4Calc ships an update every 8 months, and Fire Door Pro every 7 months. Most recently, A4Calc was updated on September 30, 2026 and Fire Door Pro on October 13, 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.*