THRESHOLD Lite: Spirit Box

A real spirit box on your phone.

THRESHOLD Lite is the lighter version of THRESHOLD, the ghost hunting app built like a field instrument. Run the sweep, turn the knobs, watch the room on one timeline and use a full EMF meter. No account, no ads, no sign-up. When you're ready to record what you hear, the full version is one tap away.

📻 The Spirit Box Sweep
Press SWEEP and THRESHOLD jumps through real recorded voices, shaped with saturation, echo and reverb. It's preset A from the full version.

SWEEP RATE sets how fast it jumps.
SQUELCH mutes everything below its level.
GAIN turns the whole rig up.

Each run lasts five minutes. Press SWEEP again for another, as many times as you like.

📊 The Visualizer
Magnetic field, sound and motion side by side on one timeline, so you can see what changed and when. The sphere in the middle lights up when two readings rise together.

🧲 EMF Meter
The classic 5-light K-II style meter, driven by your phone's built-in magnetic sensor. Peak hold, auto range and an alarm at the light you pick. The whole meter is in Lite.

🔓 What the Full Version Adds
Lite shows you the whole rig, and anything that comes with the full version is marked FULL VERSION. THRESHOLD, the full version, is sold separately on Google Play and adds:

GRAB, REC and MARK: save the last 15, 30 or 60 seconds, record until you stop, and mark moments on the timeline.
Live AI transcription on your phone, on a readout labeled ASR INTERPRETATION.
10 sound sources including your mic, 6 FX pedals, and 4 presets for your own rigs.
Clip review: loop, slow down, grade, transcribe and export.
The SLS camera, magnetic pendulum, field lamp, music box and question sessions.
The Wear OS remote.

🔒 Built for the Dark
Offline & private: no accounts, no ads, no analytics and no in-app purchases. Lite records nothing, so nothing leaves your phone.

Basement-proof: everything ships inside the app, so it works in haunted basements and dead zones with zero signal.

Download THRESHOLD Lite and take it on your next investigation.

Recent changes:
Smoother and more reliable, and the EMF meter reads the room better.