PCalc vs PQDIF Viewer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
PCalc
A powerful calculator designed for professionals and students, offering advanced features like RPN mode, multi-line display, and extensive unit conversions. It supports various number systems and includes an Apple Watch app for on-the-go calculations.
- Optional RPN mode
- Multi-line display
- Extensive unit conversions
- Paper tape
- Multiple undo/redo
- Hexadecimal, octal, binary support
- Apple Watch app
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PCalc is the powerful choice for scientists, engineers, students, programmers, or indeed anybody looking for a feature rich calculator. It includes an optional RPN mode and multi-line display, a choice of button layouts, an extensive set of unit conversions and constants, a paper tape, multiple undo and redo, engineering and scientific notation, as well as support for hexadecimal, octal, and binary calculations. Includes an Apple Watch app, so you can calculate on your wrist!
PQDIF Viewer
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PQDIF Viewer is a simple to use tool to chart Power Quality data in PQD files (IEEE 1159.3-2025). Open files from Mail, Files, or AirDrop, or tap the bundled sample to try it out. Built for power system engineers who need to inspect data on the go.
Screenshots
Verdict
The clearest difference is price: PQDIF Viewer at Free against PCalc's $9.99. PQDIF Viewer also leads on in-app purchases (none vs 4) and update cadence (every 3 days vs every 6 weeks). PCalc's advantage is device support (5 vs 3). On ads 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
PQDIF Viewer is free to download; PCalc costs $9.99 up front. PCalc sells 4 one-off in-app purchases. PQDIF Viewer asks for nothing beyond the download.
PCalc ships an update every 6 weeks, PQDIF Viewer every 3 days. The most recent releases landed on October 13, 2026 and October 8, 2026 respectively.
| Parameter | PCalc | PQDIF Viewer |
|---|---|---|
| Price | $9.99 | Free — better |
| Rating | 4.7 (770 ratings) — better | — |
| Positive reviews | 83.6% of reviews | — |
| Number of ratings | 770 — better | — |
| Update frequency | Every 6 weeks | Every 3 days — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod, Apple Watch, Vision Pro — better | iPhone, iPad, iPod |
| Requires iOS | 15.0 — better | 15.6 |
| Further details — not scored | ||
| Size | 81 MB | 4 MB |
| Age rating | 4+ | 4+ |
| Developer | TLA Systems Ltd. | Russell Patterson |
In-app purchases
PCalc
- Small Tip$0.99
- Medium Tip$1.99
- Large Tip$4.99
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- Enormous Tip$9.99
PQDIF Viewer
No in-app purchases
