HauntKeep: Ghost Hunting Kit

Grab a friend, turn out the lights, and see what the room is doing. Eighteen instruments, built from the sensors already in your phone.

HauntKeep turns your phone's real sensors into a kit of paranormal investigation instruments: SLS, an EMF meter, a spirit box, an EVP recorder, a vibration geophone, and more. Built for atmosphere, curiosity, and a good scare.

Every reading has a source, and the app shows it. A number on screen traces back to a sensor in your phone, with the steps behind it on the same screen: the live input, the baseline it is measured against, and the math in between. Values the app fetches or works out are labeled that way: the day's space weather and local conditions are fetched, and the moon phase is worked out from the date. A mode that needs hardware your phone doesn't have says so and stops.

What a reading means is yours to decide. Every mode says which kind it is: REAL for the ones that measure a physical signal, EXPERIENCE for the ones built for mood and story, on the tile, before you open it. Both kinds show their working.

THE INSTRUMENTS: each reads a sensor on your phone

• EMF Meter: your phone's real magnetometer, with a live baseline, a standard-deviation gauge, and space-weather (Kp) context so you can see when the field leaves your room's normal. • EVP Recorder: records the room to WAV with markers, then plays it back with a waveform, spectrogram, variable speed and a high-pass filter. • Sound: a live level meter and FFT spectrogram of the room. • Vibration: a geophone that turns your accelerometer into a seismograph for taps and footsteps. • Shadow: place your phone and watch for luminance and motion changes. • Dowsing Rods: two rods swung by real changes in magnetic heading. • Vision: a low-light camera enhancer. • SLS: a pose-estimation skeleton overlay on the live camera.

THE EXPERIENCES: interpretive, and each names what drives it

• Dictionary: a word engine driven by live field readings. • Phonetic (Spirit Box): a synthesized voice sweep; the field sets how busy it is, and the words come from the app's own bank. • Radio Sweep: a sweep across live internet radio. • Music Box, Morse, REM Touch, Talking Board, Draw, White Noise, and a live multi-sensor Investigation camera.

SESSIONS

• Record a baseline sweep so spikes are measured against your room's own normal. • A cross-mode timeline lines up every mode's events on one ruler and flags moments when two or more independent sensors fire within the same 2 s window. • Tag a session with real environmental context: weather, sunrise/sunset, moon phase, and the space-weather Kp index (optional; uses approximate location). • Export a session as a clean report or a shareable zip.

PRIVATE BY DESIGN

• Yours alone: no accounts, no ads, no trackers, no analytics SDKs. • Your recordings, photos, and notes stay on your device. • The one thing that ever leaves your phone is an approximate, rounded location, sent to a weather service when you tap to add environmental context. • Deleting the app removes all of its data.

FREE TO EXPLORE

Free to install, with the EMF meter and the Talking Board fully open: no time limit and no ads. The whole investigation layer is free too: sessions, the baseline sweep, the cross-mode timeline and environmental context. One optional purchase opens the remaining modes and lets you take a case file away: PDF reports, session bundles and CSV export. Pay once; there is no subscription.

WHAT TO EXPECT

The instruments read your phone's real sensors, and every value arrives with the steps behind it. HauntKeep is an entertainment app, not a scientific, medical, or safety instrument, and it makes no claim about what its readings mean. What those readings mean is left entirely to you. It contains paranormal and mild-horror themes and is intended for a general (not young child) audience.

Grab a friend, turn out the lights, and go ghost hunting.

HauntKeep™ is a trademark of Hevenis LLC.