A4Calc vs JMA America
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
A4Calc
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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
JMA America
Easily find locksmiths in your area and identify the keys you need. Access a catalog of competitor key codes and download it for offline use. Connect with locksmiths via phone or email.
- Find local locksmiths
- Identify key codes
- Competitor key reference list
- Offline key catalog download
- Contact locksmiths by phone/email
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Now it's faster and easier than ever to find a locksmith and identify the key you need. JMA offers, among others, the following functions: * A list of references with the codes of the different competitors that exist in the market. * Find locksmiths in the area where you are so you can contact us by phone or email. * The keys catalog could be downloaded to the phone, to work offline.
Screenshots
Verdict
The clearest difference is price: JMA America at Free against A4Calc's $4.99. JMA America also leads on update cadence (every 9 days vs every 8 months). A4Calc's advantage is iOS requirement (12.0 vs 26.5). On 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
JMA America 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, JMA America every 9 days. The most recent releases landed on October 26, 2026 and October 19, 2026 respectively.
| Parameter | A4Calc | JMA America |
|---|---|---|
| Price | $4.99 | Free — better |
| Rating | — | 1.0 (1 ratings) — better |
| Positive reviews | — | 0.0% of reviews |
| Number of ratings | — | 1 — better |
| Update frequency | Every 8 months | Every 9 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | — | Free |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 12.0 — better | 26.5 |
| Further details — not scored | ||
| Size | 2 MB | 10 MB |
| Age rating | 4+ | 4+ |
| Developer | Farren Domenici | Eduardo Romero |
In-app purchases
A4Calc
No in-app purchases
JMA America
No in-app purchases
Questions
Is A4Calc free?
Is JMA America free?
Do A4Calc or JMA America have ads?
Which is updated more often, A4Calc or JMA America?
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