Comparison

A4Calc vs Fire Door Pro

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

A4Calc

Features
Read full description

A4 Small Format Interchangeable Core Calculator (sister app of A2Calc and A3Calc) ---Programmed by a Locksmith, for Locksmiths--- Automatically calculates the pinning chart for A4 SFIC. Built for 6 or 7 pin systems, however, less can be achieved by using a decimal to erase a chamber. Minimum of a control and master key are required to make a chart. Additional change key available for all devices; 2 change keys available for 16:9 screen devices. Randomize function will generate completely random charts each time it is triggered. "Lock/Unlock" toggle disables/enables all inputs and functions to prevent unwanted/lost changes. Control Finder is an added bonus by reverse engineering a core to determine the control key's bitting. This is perfect when needing to remove multiple cores in a building when the control key has been lost. There are two methods for achieving the control key: 1. using the master, control, and bottom pins, or 2. using only the top/driver pins. Up to 16 different projects can be saved at any one given time. All projects are encrypted and protected with a passcode when stored on your device. All projects can be exported via AirPrint and Email. Compatibility: iPhone / iPod touch on iOS 8.0 or later and iPad on iOS 12.0 or later. Found a bug? Something not working? Have a suggestion? Feel free to contact me via email: farren@phoxlocks.com

About

Fire Door Pro

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
Read full description

Can’t afford to hire a professional door inspector to perform your door inspections? Are you a general contractor who needs to just perform a small amount of door inspections for commissioning of a new health care project? OR are you a professional inspector who wants to save a few minutes per door inspection to maximize efficiency in the field and are tired of the countless hours trying to gather report data? This app was developed specifically for you. Use Fire Door Inspector Pro App to gather data and produce either an electronic or hard copy report for 13 point NFPA 80 Rated Swinging Fire Door Inspections. Whether you are a certified inspector, facility maintenance personnel, or general contractor with working knowledge of doors and their hardware, this app will save you both time and money. The app collects vital door information that can be easily accessed and revisited annually. It follows the NFPA 80 - 13 point inspection and produces an instantaneous report that can be either emailed electronically or printed. The app allows you to upload photos of each door or deficiency, make door specific notes that can be relayed back to the client.specifically, and lists the specific code that needs corrected. The app was specifically designed to make the door inspection process systematic, with built in safeguards to ensure you don’t miss any of the sub-categories in the 13 point door inspection.

Screenshots

A4Calc4 screens
Fire Door Pro3 screens

Verdict

The call

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.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

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.

UpkeepUpdate frequency

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.

Scorecard2 real differences · 8 level
A4Calc versus Fire Door Pro: the parameters behind the verdict, then further details
ParameterA4CalcFire Door Pro
Price$4.99Free — better
Rating—3.0 (2 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—2 — better
Update frequencyEvery 8 monthsEvery 7 months — better
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.0 — better15.1
Further details — not scored
Size2 MB41 MB
Age rating4+4+
DeveloperFarren DomeniciDebra Bragg

In-app purchases

None

A4Calc

No in-app purchases

None

Fire Door Pro

No in-app purchases

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.

Other comparisons