HP16C vs Hz Lab

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

Hz Lab puts mosquito tones, speaker water eject and a frequency generator into one simple tool. No ads. No subscription. The paid features are a single one-time purchase. MOSQUITO TONE Nine steps from 8,000Hz to 20,000Hz, playing the moment you tap. Every step is free. Each frequency comes with a rough guide to the age that usually still hears it, which makes it easy to compare with friends and family. HEARING CHECK Tones play from low to high and you answer "I hear it" or "I don't". You get a rough idea of where your hearing tops out. WATER EJECT For when water gets into the speaker. Pulsed low tones around 165Hz move the diaphragm far enough to help push droplets out. A countdown and waveform show you exactly how long is left. FREQUENCY GENERATOR Anything from 20Hz to 20,000Hz, by slider or by typing the number. The full range is free with a sine wave. SOLFEGGIO AND BINAURAL BEATS Solfeggio frequencies from 174Hz to 963Hz, plus binaural beats that play slightly different tones in each ear. HZ LAB PRO (one-time purchase) - Tune in 1Hz steps - Square, triangle and sawtooth waveforms - Strong and quiet water eject courses, with adjustable timing and range - Full control over binaural beats - All nine Solfeggio frequencies - Unlimited presets (the free version keeps three) - Sleep timer and background playback - Hearing check history and per-ear testing Pay once and keep it. Nothing auto-renews. WHAT WE TELL YOU UP FRONT - The iPhone's built-in speaker drops off sharply above about 16,000Hz. Use headphones for high frequencies. The app says the same thing. - Water eject does not guarantee that all water is removed, does not improve water resistance, and does not repair a water-damaged device. - The hearing check and age guidance are informational only, not a substitute for a medical hearing test. PROTECTING YOUR HEARING High tones rarely feel loud but still strain your ears. By default Hz Lab caps the volume above 15,000Hz and while headphones are connected (adjustable in Settings), and playback stops automatically if your headphones are unplugged. PRIVACY No account needed. No personal data is collected at all. No advertising or analytics SDKs. Presets and hearing check results stay on your device.