r.Calc vs Complex RPN Calculator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
r.Calc
A straightforward calculator utilizing Reverse Polish Notation (RPN) for everyday calculations. It offers a four-level visible stack with a total capacity of 100 positions, providing visual feedback on stack fullness. Basic arithmetic operations and stack manipulation functions are included.
- Reverse Polish Notation (RPN) input
- Four visible stack levels
- 100-position stack capacity
- Progress bar for stack fullness
- Basic arithmetic operations
- Stack swap and recall functions
- Vibration feedback for errors
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This classic RPN (Reverse Polish Notation) calculator is a simple calculator for daily uses. The calculator features a four visible level stack, the total stack size has a total of hundred positions. A progress bar on the top of the screen shows you how the stack is full. For now the implemented operations are; Plus, Minus, Multiply, Divide, Opposite, Inverse. Other facilities like swap the first two number in the stack and recall from the last operation the two arguments should simplify the life. All keyboard errors are notified by a vibration.
Complex RPN Calculator
This scientific calculator utilizes a four-level stack and natively handles complex numbers. It allows users to input and view numbers in both polar and rectangular formats, remembering its state and offering 10 memory locations.
- Complex number support
- Four-level stack
- Polar and rectangular formats
- State persistence
- 10 memory locations
- Scientific calculations
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Complex RPN Calculator is a scientific RPN calculator with a four stack whose native number is complex. You can view and enter numbers in both polar and rectangular formats. Complex RPN remembers its state between usages and has 10 memory locations.
Screenshots
Verdict
r.Calc and Complex RPN Calculator both sit at 4.0 stars, but that hides the real split: 100% of r.Calc's written reviews are positive against 52% of Complex RPN Calculator's. r.Calc also leads on iOS requirement (2.2.1 vs 16.4). Complex RPN Calculator's advantage is price (Free vs $0.99) and update cadence (every 5 months vs every 197 months). On rating, ads, 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
Complex RPN Calculator is free to download; r.Calc costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
On the App Store both sit at effectively the same score — 4.0 for r.Calc against 3.9 for Complex RPN Calculator. That said, the two scores are not equally well evidenced: Complex RPN Calculator has 24 ratings behind it against 3, so its average is the more settled of the two. Written reviews are what separate them: 100% of r.Calc's written reviews are positive against 52% of Complex RPN Calculator's.
r.Calc ships an update every 197 months, Complex RPN Calculator every 5 months. The most recent releases landed on June 10, 2026 and October 21, 2026 respectively.
| Parameter | r.Calc | Complex RPN Calculator |
|---|---|---|
| Price | $0.99 | Free — better |
| Rating | 4.0 (3 ratings) — better | 3.9 (24 ratings) |
| Positive reviews | 100.0% of reviews — better | 51.7% of reviews |
| Number of ratings | 3 | 24 — better |
| Update frequency | Every 197 months | Every 5 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 2.2.1 — better | 16.4 |
| Further details — not scored | ||
| Size | 0 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | Nicolas Jorand | John Coddington |
Customer experience
r.Calc
Complex RPN Calculator
Bugs and requests
r.Calc
Not enough reviews yet to summarise bugs or requests.
Complex RPN Calculator
Reported bugs
6 issues- Mutes other apps when used
- Slow keyboard response after update
- X^3 calculation incorrect for large imaginary numbers
- App crashes on opening/button press (historical iOS 9 issues)
- App starts upside down in landscape on iPad (historical iOS 8 issue)
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- Unreadable fonts on iPad (historical version 1.2 issue)
Requested features
24 requests- Turn off key click sound
- Customize number display
- See the stack
- Fix slow entry response
- Fix imaginary number calculation (X^3)
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- Improve SwiftUI design (less whitespace)
- Show all stack levels
- Add angle function
- Add magnitude function
- Add 'Clear X' button
- Make RAD/DEG toggle button
- Single button for Sci/Eng/Fix/Raw modes
- Add '//' (parallel) function
- Add 'Module' button
- Change 'i' to 'j' for imaginary part
- Show stack levels
- Add log2 function
- Add logGamma function
- Smaller buttons
- Add complex conjugate button
- Add real part button
- Add imaginary part button
- Add modulo function
- Make app start faster
In-app purchases
r.Calc
No in-app purchases
Complex RPN Calculator
No in-app purchases
