Complex RPN Calculator vs ODE Solver +
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
ODE Solver +
This utility app calculates ordinary differential equations using the Runge-Kutta method. It offers a step width of 0.01 for its calculations.
- Ordinary differential equation calculation
- Runge-Kutta method
- Step width 0.01
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It is calculated using Runge-Kutta method (step width 0.01).
Screenshots
Verdict
The clearest difference is ads: Complex RPN Calculator at none against ODE Solver +'s shown. Complex RPN Calculator also leads on monetization model (free vs ad-supported) and ratings volume (24 vs 4). ODE Solver +'s advantage is update cadence (weekly vs every 5 months) and iOS requirement (14.0 vs 16.4). On price, rating, 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
On the App Store both sit at effectively the same score — 3.9 for Complex RPN Calculator against 4.0 for ODE Solver +. That said, the two scores are not equally well evidenced: Complex RPN Calculator has 24 ratings behind it against 4, so its average is the more settled of the two.
Complex RPN Calculator ships an update every 5 months, ODE Solver + weekly. The most recent releases landed on October 21, 2026 and October 24, 2026 respectively.
| Parameter | Complex RPN Calculator | ODE Solver + |
|---|---|---|
| Price | Free | Free |
| Rating | 3.9 (24 ratings) | 4.0 (4 ratings) — better |
| Positive reviews | 51.7% of reviews | — |
| Number of ratings | 24 — better | 4 |
| Update frequency | Every 5 months | Weekly — better |
| Ads | No — better | Yes |
| In-app purchases | No | No |
| Monetization | Free — better | Ad-supported |
| Devices | iPhone, iPad | iPhone, iPod |
| Requires iOS | 16.4 | 14.0 — better |
| Further details — not scored | ||
| Size | 1 MB | 11 MB |
| Age rating | 4+ | 4+ |
| Developer | John Coddington | Takahiko Nakade |
Customer experience
Complex RPN Calculator
ODE Solver +
Bugs and 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
ODE Solver +
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Complex RPN Calculator
No in-app purchases
ODE Solver +
No in-app purchases
Questions
Is Complex RPN Calculator free?
Is ODE Solver + free?
Which has better reviews, Complex RPN Calculator or ODE Solver +?
Do Complex RPN Calculator or ODE Solver + have ads?
Which is updated more often, Complex RPN Calculator or ODE Solver +?
Other comparisons
