Calx vs Calc Pro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Calx
This calculator app utilizes Reverse Polish Notation (RPN) for efficient calculations by manipulating numbers on a stack. It offers a guided tutorial, gestural interaction, multiple keypads with various functions, and customization options for fonts and colors.
- Reverse Polish Notation (RPN)
- Gestural interaction
- Multiple keypads (basic, scientific, statistical)
- Customizable fonts and colors
- Guided tutorial
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CALX is an RPN calculator — a calculator designed to work with a list of numbers. This means that instead of just typing an equation into your calculator, you push numbers onto a stack, and then apply operations to the lowermost numbers in the stack. It's bizarre, but it makes sense once it clicks. If this all sounds confusing, don't worry! CALX comes with a guided tutorial which will get you up to speed in three minutes. Features: • Gestural interaction: Manipulate your data with simple, intuitive gestures. • Multiple keypads: CALX features an array of basic, scientific, and statistical functions. • Customization: Select from different fonts and colours to find a combination that works for you.
Calc Pro
This powerful calculator handles complex equations and huge numbers with up to 15 digits of precision. It saves your calculation history, allowing you to reuse previous equations and answers. Access scientific functions like square root and logarithms easily with a swipe.
- Complex calculations
- Huge number handling
- Calculation history
- Scientific functions
- Dark Mode
- Copy answer
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Calc Pro can do complicated calculations easily. It is a very powerful math calculator but easy to use. Calc Pro also handles huge numbers without ellipsis. Most calculators will only handle calculations involving numbers with up to 13 digits, but this one allows for larger and more precise calculations, supporting up to 15 digits of precision to the right of the decimal, and big enough digits to the left. Calculation history won't be lost when the app is closed. You can reuse calculation equations and answers by tapping. Calc Pro also supports mathematical functions like square root, logarithm, combinations, and permutation. You can easily access these functions by swiping. Features: - Arithmetic - Calculation with parentheses - Dark Mode - Huge Number Handling - Copy calc answer with a long press - Calculation history - Scientific calculation - Swipe to change the keyboard easily
Screenshots
Verdict
The clearest difference is price: Calc Pro at Free against Calx's $0.99. Calc Pro also leads on update cadence (monthly vs every 24 months). Calx's advantage is ads (none vs shown) and rating (5.0 vs 4.8). On review sentiment, ratings volume, 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
Calc Pro is free to download; Calx costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Calx holds the better App Store score, 5.0 against 4.8. Both are backed by a comparable volume of ratings — 2 and 5 respectively. Written reviews split almost evenly too, at 100% and 100% positive.
Calx ships an update every 24 months, Calc Pro monthly. The most recent releases landed on August 12, 2026 and September 21, 2026 respectively.
| Parameter | Calx | Calc Pro |
|---|---|---|
| Price | $0.99 | Free — better |
| Rating | 5.0 (2 ratings) — better | 4.8 (5 ratings) |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| Number of ratings | 2 | 5 — better |
| Update frequency | Every 24 months | Monthly — better |
| Ads | No — better | Yes |
| In-app purchases | No | No |
| Monetization | Paid | Ad-supported — better |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 12.0 — better | 18.0 |
| Further details — not scored | ||
| Size | 4 MB | 8 MB |
| Age rating | 4+ | 4+ |
| Developer | Daniel Clelland | Keita Nonaka |
Customer experience
Calx
Calc Pro
In-app purchases
Calx
No in-app purchases
Calc Pro
No in-app purchases









