XSpecApp vs Physics Constants Library
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
XSpecApp
This application displays EDXRF spectra, allowing users to manually identify elements, calculate ROIs, and add annotations. It supports saving, loading, and printing spectra with detailed information. The app can also acquire spectra using a digital pulse processor via USB, Serial, or wireless connections.
- Manual element identification
- ROI calculation for peaks
- Spectrum annotations
- Spectrum printing with ROIs
- Save and load spectra
- Acquire spectra via digital pulse processor
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XSpecApp displays EDXRF spectra providing the following capabilities: * Manual identification of elements * ROI (integrals) for identified peaks * Annotations on spectrum * Printing of spectrum with calculated ROIs * Saving and Loading of spectrum, with annotations and element information * NEW: Acquire spectra using an Amptek DP5 digital pulse processor. Supported interfaces are USB, Serial, and XSpecConnect (Wi-Fi and Bluetooth) . Please visit www.xrfconsulting.com for details on XSpecConnect.
Physics Constants Library
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Discover the building blocks of our universe with Physics Constants Library – the ultimate reference and learning tool for students, educators, and professionals. Whether you’re preparing for exams, teaching in the classroom, or working on research, this app puts the most important physics constants and tools at your fingertips. What You’ll Get • 20+ Fundamental Constants – Gravity, Planck’s constant, electron charge, speed of light, and more. • Smart Search & Filters – Quickly find constants by name, symbol, or value. • Multi-Unit Support – Switch between SI, CGS, Imperial, and other unit systems. • Interactive Learning – Use flashcards, quizzes, and study modes to strengthen memory. • Professional Tools – Unit converter, calculator, and built-in formula helper. • Offline Access – Access all content anytime, without internet. Key Features Constants Library • Covers mechanics, quantum physics, thermodynamics, electromagnetism, and more. • Includes historical context, real-world applications, and related concepts. Learning Center • Flashcards with smart repetition for long-term retention. • Quizzes with adjustable difficulty levels. • Study progress tracking to stay motivated. Professional Tools • Advanced unit converter with 25+ categories. • Scientific calculator with constants built-in. • Formula helper to apply equations instantly. Modern Experience • Clean, elegant interface designed for clarity. • Dark mode, 10 app themes - System, Light, Dark, Cosmic, Quantum, Sunset, Ocean, Forest, Aurora, Midnight and accessibility support. • Favorites tab for quick access to your most-used constants. Perfect For • Students – Learn and memorize constants with ease. • Teachers – Enhance lessons with interactive study tools. • Researchers & Engineers – Reliable, quick reference during work. • Enthusiasts – Explore the fundamental constants that shape our world. Data Accuracy You Can Trust All values are based on CODATA 2018 recommendations and NIST standards, ensuring precision for both academic and professional use. Upgrade for More Unlock premium to access advanced study modes, unlimited practice, and detailed progress analytics. Download Physics Constants Library today and take your physics knowledge to the next level!
Screenshots
Verdict
The clearest difference is ads: XSpecApp at none against Physics Constants Library's shown. XSpecApp also leads on update cadence (every 2 days vs every 7 months) and device support (3 vs 1). On price and in-app purchases 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
Both are free to download. XSpecApp sells 1 one-off in-app purchase and Physics Constants Library sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.
XSpecApp ships an update every 2 days, Physics Constants Library every 7 months. The most recent releases landed on September 27, 2026 and September 20, 2026 respectively.
| Parameter | XSpecApp | Physics Constants Library |
|---|---|---|
| Price | Free | Free |
| Rating | 3.5 (2 ratings) — better | — |
| Number of ratings | 2 — better | — |
| Update frequency | Every 2 days — better | Every 7 months |
| Ads | No — better | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod — better | iPhone |
| Requires iOS | 8.0 — better | 18.4 |
| Further details — not scored | ||
| Size | 48 MB | 10 MB |
| Age rating | 4+ | 4+ |
| Developer | Brian Cross, XRF Consulting, LLC | ChatStick Company Limited |
In-app purchases
XSpecApp
- XSpecApp$24.99
Physics Constants Library
- Unlock All Features$2.99
Questions
Is XSpecApp free?
Is Physics Constants Library free?
Do XSpecApp or Physics Constants Library have ads?
Which is updated more often, XSpecApp or Physics Constants Library?
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