Comparison

PLCLink vs DB40X

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

Head to head
About

PLCLink

Features
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Supervision application for PLC or other URL command device. Particularly intended for supervision integrators, for research laboratory, up to end user or home remote. PLCLink can read and write one or more accessible PLC over Internet with ModBus or HTTP protocols and is well adapted for numerical results presentation. You just add a XML file inside app documents folder or inside PLC folder, some web page help you for this work. Transfert between PLC and application with ModBus (502) or HTTP (80) format. WAGO PLC are full compatibles because of SSI capabilities but some other ModBus PLC can be used to. • Configuration are easy to send for end user with a email. • Cell value can be send by email. (IFTTT action). • A room can be protected with a PIN code. • DropBox can help you for file storage. • QR Code can load wagoML source with plclink:// protocol. • Data can be saved in a .csv file. • Modbus record transfert mode for easy debug. • Modbus can now be synchronous for Schneider PLC. • Many data representation : text, days, month, bits and explicit icon. • A colorPicker for setting RGB lamp. • Push notification. • Action with javascript objects into iFrame. IPad version is very powerful with self editor for wagoML local file. PLCLink questions regularly this file (2s) and display results in a specific room window. This file comes with WagiML format, you will find a description here : http://pautex.fr/plclink/wagoml.php Entries can be saved and email up to final destination client, very easy to managed. This version allows playback of information by a url, the answer is direct text reply or included in an xml or JSON structure. These mode are ready good for small device as MBED and Raspberry PI. PUSH notification You choose a random 10+ digits number and simply with reading a specific URL you send calls to iPhones recorded with this number. All PLCs connected to the Internet are capable of producing this notification. Development : Pautex JF ¢ Pautex 2011-2024, NANCY

About

DB40X

A high-precision scientific calculator inspired by the HP48 series, offering arbitrary precision computations, complex numbers, vectors, matrices, and graphing. It supports RPN and algebraic operations, with over 1000 built-in functions and a hyperlinked help system.

Highlights
  • Arbitrary precision computations
  • RPN and algebraic operations
  • Complex numbers, vectors, and matrices
  • Graphing and plotting
  • Engineering units and conversions
  • Hyperlinked help system
Features
Read full description

DB40X is a high-precision scientific calculator compatible with DB48X and inspired by the legendary HP48 series from Hewlett-Packard. It is not an emulator, but a redesign from scratch, which is faster, and delivers never seen before capabilities like computations in arbitrary precision. Like the original HP48, DB40X supports an unlimited stack, RPN and algebraic operations, complex numbers, based numbers, vectors, matrices, text, symbolic computations, numerical solving and integration, graphing and plotting, statistics, engineering units, and well over 1000 built-in functions. DB40X adds several HP50G capabilities, including a library of equations and constants covering mathematics, physics or chemistry. Using modern technologies, DB40X goes well beyond the original HP48 in many ways: - It is significantly faster, uses less memory, and features a higher-resolution 240x400 pixels graphical display. - Integer and decimal values can have an arbitrarily large number of digits, so you can compute log(pi) with 200 digits in a few keystrokes. - The six function keys feature up to three function per key, giving quick access to up to 18 related functions at a time. - Complex numbers can mix and match polar and rectangular form. - Symbolic operations extend to complex numbers, vectors and matrices. - Based numbers can be in any base from 2 to 36, and support any number of bits, making it easy to emulate a 23-bit or 512-bit processor. - Text is represented using Unicode instead of the proprietary HP encoding, facilitating data exchange with the rest of the world. - Multiple graphs can be distinguished using bitmap patterns. - Engineering units include all the modern evolutions of the SI system, and can be configured by the user, e.g. to integrate currency units with the exchange rate du jour. Converting between USD/hour and EUR/day has never been so easy! - A built-in hyperlinked help system documents functions simply by holding the corresponding key, and combine a quick start guide, a user manual and a reference manual. DB40X will run many user RPL programs as is. However, since it is not an emulator, it will not run any HP binary object, and notably will not run HP48 games or anything involving system RPL. Version 0.7.14 is an early-access release. Please consult https://github.com/c3d/db48x/blob/stable/doc/5-Unimplemented.md for a list of HP48 commands that are not yet implemented. DB40X is part of a family of compatible RPL calculators that include DB48X and DB50X. DB40X lacks the ability to write programs or data to disk, and RPL programs are limited to 40K.

Screenshots

PLCLink4 screens
DB40X3 screens

Verdict

The call

The clearest difference is price: DB40X at Free against PLCLink's $8.99. DB40X also leads on update cadence (every 3 weeks vs every 2 months). PLCLink's advantage is iOS requirement (12.0 vs 14.0). 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

CostPrice · In-app purchases · Ads · Monetization

DB40X is free to download; PLCLink costs $8.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

PLCLink ships an update every 2 months, DB40X every 3 weeks. The most recent releases landed on September 28, 2026 and October 3, 2026 respectively.

Scorecard3 real differences · 7 level
PLCLink versus DB40X: the parameters behind the verdict, then further details
ParameterPLCLinkDB40X
Price$8.99Free — better
Rating—4.7 (7 ratings) — better
Positive reviews—66.7% of reviews
Number of ratings—7 — better
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.0 — better14.0
Further details — not scored
Size4 MB7 MB
Age rating17+4+
DeveloperJean-Francois PautexChristophe de Dinechin

In-app purchases

None

PLCLink

No in-app purchases

None

DB40X

No in-app purchases

Questions

Is PLCLink free?
PLCLink costs $8.99, with no in-app purchases.
Is DB40X free?
DB40X is free to download, with no in-app purchases.
Do PLCLink or DB40X have ads?
Neither PLCLink nor DB40X shows ads.
Which is updated more often, PLCLink or DB40X?
PLCLink ships an update every 2 months, and DB40X every 3 weeks. Most recently, PLCLink was updated on September 28, 2026 and DB40X on October 3, 2026.

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