Calccis vs HP
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Calccis
This utility app offers advanced calculations using reverse Polish notation. It supports a wide range of functions including trigonometry, logarithms, and matrix operations for real, fractional, and complex numbers. An undo stack allows for up to 100 operations to be reversed.
- Reverse Polish Notation (RPN)
- Basic arithmetic
- Trigonometrical functions (degrees/radians)
- Logarithm and exponent calculations
- Real, fractional, and complex number support
- Matrix calculations
- Undo/Redo stack (100 operations)
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Calccis is a reverse polish notation (RPN) calculator. It supports basic arithmetic, trigonometrical, logarithm and exponent calculations for real, fractional, and complex numbers. Degrees and radians can be used for trigonometrical functions. You can perform matrix calculations, too. There is an undo stack, which supports undoing and redoing the 100 latest operations. Calccis does not copy or mimic any existing physical calculators. However, the operation of the stack has been influenced by how the stack works in the 1990s Hewlett-Packard HP-48 family of calculators.
HP
Emulates classic Hewlett Packard RPN scientific calculators from the 1970s. Experience the original HP-35, HP-45, and HP-21 models on your iPhone.
- RPN calculator emulation
- HP-35 model
- HP-45 model
- HP-21 model
- Classic scientific calculator interface
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The classic Hewlett Packard RPN (Reverse Polish Notation) calculators. - HP-35, HP-45. First pocket scientific calculators (1972). - HP-21. 2nd gen of the HP-35 (1975)
Screenshots
Verdict
The clearest difference is rating: Calccis at 5.0 against HP's 4.6. HP's advantage is ratings volume (66 vs 1). On price, update cadence, ads 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. Neither carries in-app purchases, so what you see is what you pay.
Calccis holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: HP has 66 ratings behind it against 1, so its average is the more settled of the two.
Calccis ships an update every 3 weeks, HP every 11 days. The most recent releases landed on November 3, 2026 and November 14, 2026 respectively.
| Parameter | Calccis | HP |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | 4.6 (66 ratings) |
| Positive reviews | — | 100.0% of reviews |
| Number of ratings | 1 | 66 — better |
| Update frequency | Every 3 weeks | Every 11 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 17.6 | 17.2 — better |
| Further details — not scored | ||
| Size | 1 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | Jukka Aittola | Enrique Haro |
In-app purchases
Calccis
No in-app purchases
HP
No in-app purchases
