Comparison

QRwidget vs LineKeeper

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

Head to head
About

QRwidget

Place your QR code directly on your home screen as a widget for instant access. Scan, enter, or upload QR codes with a simple and streamlined interface. Always have your QR code readily available without navigating through multiple apps.

Highlights
  • Home screen QR code widget
  • Scan existing QR codes
  • Manually enter QR code data
  • Upload QR code images
  • Simple and streamlined interface
  • Always accessible QR code
Features
Read full description

QRwidget is a unique app designed to simplify your QR code experience. Its primary function? To place your QR code directly on your home screen, making it easily accessible and highly visible. DISPLAY WITH EASE: QRwidget allows your QR code to be placed on your home screen as a widget, ready to be scanned whenever it's needed. No more navigating through multiple apps to access your QR code. SCAN, ENTER, OR UPLOAD: With QRwidget you can scan an existing QR code, manually enter data, or upload a picture of a QR code. QRwidget makes the process seamless and effortless. ALWAYS AT HAND: With QRwidget, your QR code is always just a glance away. It's the ultimate convenience - no more searching through apps or scrolling through photos. SIMPLE AND STREAMLINED: QRwidget is designed to be as straightforward as it is useful. No clutter, no confusion, just your QR code, right where you need it. Experience the simplicity and convenience of QRwidget today. Download it and enjoy the ease of having your QR code right on your home screen! Contact us at hello@qrcardapp.com Follow us on Facebook | Instagram | Twitter: qrcardapp

About

LineKeeper

Features
Read full description

LineKeeper turns your iPhone into a pocket HMI for the controllers on your plant floor — Allen-Bradley Logix, Siemens S7, and anything that speaks Modbus TCP. Scan the network and the app finds every PLC around and tells you which ones are ready to talk. On Allen-Bradley it reads the controller's own tag list over EtherNet/IP — live values in seconds, nothing to configure: no PLC program changes, no gateway, no OPC server, no cloud account. Values go straight from the controller to your phone. WHAT YOU CAN DO • Zero-config tag browser on Logix — every tag of every PLC, live, with search, including program-scoped tags. • Find by action — don't know the address? Press the machine's real button, or nudge a setpoint on its own screen, in the rhythm the app dictates — and the app finds the tag that followed. Works on Modbus and S7 too, where there are no tag names at all. • Network scan — one sweep fingerprints EtherNet/IP, Modbus TCP, S7 and more. A PLC with closed access shows as "found, access closed" with the exact steps to open it, down to the TIA Portal clicks. • One dashboard per machine, on multiple pages — number, gauge, LED and trend tiles on swipeable named pages ("Filler", "Capper", "Conveyors"), even when one machine runs several PLCs. • Operator panel — large start/stop buttons, hold-to-run jog, latches, setpoints and status lamps, full-screen kiosk mode with the screen kept awake. • Alarms and status codes — alarm words mapped to operator texts, a red banner over every screen while an alarm is active, and a session journal of appeared/cleared. • Machine history — a parameter snapshot of the controller taken at the first connection, plus a change log of every dashboard and panel tag: date and value of each change, kept on the phone across sessions. • Guarded writes — every write is confirmed and validated against the tag type and limits; hold-to-run releases the moment the app loses focus. • Machine profiles — PLCs, register maps, pages, panel and alarm texts saved as one profile and shared as a file: enter the register map once, the next shift sees names. • Built-in demo line — two virtual PLCs with a working panel so you can learn the whole app with no hardware. LINEKEEPER PRO (IN-APP PURCHASE) Reading is free forever. A one-time Pro purchase unlocks, on real controllers: writing setpoints and driving the operator panel, plus machine history — the parameter snapshot and the per-tag change log. Everyone who bought Write Unlock owns Pro automatically. The demo line includes every Pro feature free. WHO IT'S FOR Controls engineers, integrators and maintenance techs who need a quick window into a controller during commissioning, troubleshooting, or a line-down call — without carrying a laptop. HOW IT CONNECTS Your phone must be on the same network as the controller (plant Wi-Fi that routes to the PLC, or a USB-C Ethernet adapter). There is no cloud relay: if you can ping the PLC, the app can connect. SUPPORTED CONTROLLERS • Allen-Bradley CompactLogix and ControlLogix (the tag-based Logix 5000 family) over EtherNet/IP; SLC-500 and MicroLogix over PCCC, with the major fault decoded in place; PLC-5 via the address book (experimental). • Siemens S7-300 and S7-400 out of the box; S7-1200 and S7-1500 with PUT/GET enabled and non-optimized DBs — the app shows the exact TIA Portal steps. Absolute addressing: DB, M, I/Q. • Modbus TCP devices — Schneider, VFDs, energy meters, WAGO, Delta and other Modbus slaves, with per-connection unit ID and word-order settings. Micro800, LOGO! and S7-200 use different protocols and are not supported yet. SAFETY Writing a value can move real machinery. You remain responsible for safe operation and must follow all site safety procedures. Never rely on the app for an emergency stop or any safety function. See the full terms at linekeeper.net/terms.html.

Screenshots

QRwidget3 screens
LineKeeper4 screens

Verdict

The call

The clearest difference is price: LineKeeper at Free against QRwidget's $0.99. LineKeeper also leads on update cadence (monthly vs every 20 months). QRwidget's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement 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

LineKeeper is free to download; QRwidget costs $0.99 up front. LineKeeper sells 1 one-off in-app purchase. QRwidget asks for nothing beyond the download.

UpkeepUpdate frequency

QRwidget ships an update every 20 months, LineKeeper monthly. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard3 real differences · 6 level
QRwidget versus LineKeeper: the parameters behind the verdict, then further details
ParameterQRwidgetLineKeeper
Price$0.99Free — better
Rating5.0 (3 ratings) — better—
Number of ratings3 — better—
Update frequencyEvery 20 monthsMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS15.115.0 — better
Further details — not scored
Size34 MB22 MB
Age rating4+4+
DeveloperLukas HechenbergerOleksandr Makarov

In-app purchases

None

QRwidget

No in-app purchases

1 purchases

LineKeeper

One-time1
  • Write Unlock$59.99

Questions

Is QRwidget free?
QRwidget costs $0.99, with no in-app purchases.
Is LineKeeper free?
LineKeeper is free to download, with in-app purchases available.
Do QRwidget or LineKeeper have ads?
Neither QRwidget nor LineKeeper shows ads.
Which is updated more often, QRwidget or LineKeeper?
QRwidget ships an update every 20 months, and LineKeeper monthly. Most recently, QRwidget was updated on November 3, 2026 and LineKeeper on October 31, 2026.

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