Comparison

XSpecApp vs Physics Constants Library

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

Head to head
About

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.

Highlights
  • Manual element identification
  • ROI calculation for peaks
  • Spectrum annotations
  • Spectrum printing with ROIs
  • Save and load spectra
  • Acquire spectra via digital pulse processor
Features
Read full description

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.

About

Physics Constants Library

Features
Read full description

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

XSpecApp1 screens
Physics Constants Library4 screens

Verdict

The call

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

CostPrice · In-app purchases · Ads · Monetization

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.

UpkeepUpdate frequency

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.

Scorecard4 real differences · 5 level
XSpecApp versus Physics Constants Library: the parameters behind the verdict, then further details
ParameterXSpecAppPhysics Constants Library
PriceFreeFree
Rating3.5 (2 ratings) — better—
Number of ratings2 — better—
Update frequencyEvery 2 days — betterEvery 7 months
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS8.0 — better18.4
Further details — not scored
Size48 MB10 MB
Age rating4+4+
DeveloperBrian Cross, XRF Consulting, LLCChatStick Company Limited

In-app purchases

1 purchases

XSpecApp

One-time1
  • XSpecApp$24.99
1 purchases

Physics Constants Library

One-time1
  • Unlock All Features$2.99

Questions

Is XSpecApp free?
XSpecApp is free to download, with in-app purchases available.
Is Physics Constants Library free?
Physics Constants Library is free to download, with in-app purchases available.
Do XSpecApp or Physics Constants Library have ads?
Physics Constants Library shows ads; XSpecApp does not.
Which is updated more often, XSpecApp or Physics Constants Library?
XSpecApp ships an update every 2 days, and Physics Constants Library every 7 months. Most recently, XSpecApp was updated on September 27, 2026 and Physics Constants Library on September 20, 2026.

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