HP16C vs my15c
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
HP16C
This app faithfully recreates the legendary HP 16C Computer Scientist calculator, offering advanced hex arithmetic, bit manipulation, and base conversion. It features RPN, keystroke programming, and modern enhancements like a two-line display and haptic feedback.
- Full RPN calculator
- Integer arithmetic (HEX, DEC, OCT, BIN)
- Configurable word size (1-64 bits)
- Complete bit operations
- Keystroke programming
- Two-line display
- Haptic feedback
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A faithful recreation of the legendary HP 16C Computer Scientist calculator for iPhone, with a few modern upgrades. If you've ever needed to perform hex arithmetic, bit manipulation, or base conversion on your phone and been frustrated by the available options, this is for you. RPN-16C gives you the full power of the original HP 16C in your pocket. WHAT IT DOES - Full RPN (Reverse Polish Notation) calculator - Integer arithmetic in HEX, DEC, OCT, and BIN - Configurable word size from 1 to 64 bits - Unsigned, one's complement, and two's complement modes - Complete bit operations: shift, rotate, rotate through carry, AND, OR, XOR, NOT, mask, bit set/clear/test, count bits, left justify - Float mode with configurable precision (FLOAT 0-9) - Keystroke programming with labels, subroutines, loops, and conditionals - Storage registers with direct and indirect addressing - Programs can be imported from text (long-press the display to paste) ENHANCEMENTS OVER THE ORIGINAL - Two-line display: see both X and Y registers at once. No more guessing what's on the stack. - Wider LCD: displays all 32 bits in binary without scrolling. The original could only show 8 at a time. - Haptic feedback on every key press - State persistence: pick up right where you left off - SHOW function to peek at values in other bases FAIR WARNING This is a quirky calculator. It uses Reverse Polish Notation, has no equals key, and expects you to know what two's complement means. If you're looking for a simple calculator, this is not it. If you've ever wished you could do a bitwise rotate through carry on your phone, welcome home. DESIGNED FOR PROGRAMMERS The key layout matches the physical HP 16C exactly, including the f (gold) and g (blue) shift labels. If you know the original, you already know this one. The original HP 16C Owner's Handbook is freely available on the Internet Archive: https://archive.org/details/hp-16c_handbook
my15c
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my15C is a faithful emulation of the classic 15C — the legendary RPN scientific programmable calculator, running the original Voyager-series microcode ROM, cycle-accurate. Built for engineers, scientists, and RPN enthusiasts who want the real thing in their pocket — not just a look-alike. FEATURES • Authentic 15C ROM emulation — same logic, same quirks as the original 1982 hardware • Full RPN entry with a 4-level stack • Complex number arithmetic • Matrix operations • Numerical integration (∫f(x)) • Root solving (SOLVE) • Full programmability — write, edit, and run your own programs • Continuous memory with iCloud sync across your devices • Authentic 7-segment LCD display and keyboard layout • Landscape-optimized for iPhone, iPad, and Mac
Screenshots
Verdict
The clearest difference is in-app purchases: HP16C at none against my15c's 1. HP16C also leads on iOS requirement (17.0 vs 26.0). my15c's advantage is update cadence (every 2 days vs every 8 days). On price, ads 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. my15c sells 1 one-off in-app purchase. HP16C asks for nothing beyond the download.
HP16C ships an update every 8 days, my15c every 2 days. The most recent releases landed on September 21, 2026 and September 14, 2026 respectively.
| Parameter | HP16C | my15c |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (2 ratings) — better | — |
| Number of ratings | 2 — better | — |
| Update frequency | Every 8 days | Every 2 days — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free | — |
| Devices | iPhone, iPad | iPhone, iPad, Mac — better |
| Requires iOS | 17.0 — better | 26.0 |
| Further details — not scored | ||
| Size | 1 MB | 53 MB |
| Age rating | 4+ | 4+ |
| Developer | Michael Doornbos | Miroslav Perovic |
In-app purchases
HP16C
No in-app purchases
my15c
- Unlock Full App$9.99








