BreathPrint Get notified

Coming soon to iPhone

Know Your Normal. Hear What Changes.

Record your breathing when you're well, and BreathPrint saves it as your personal baseline: five chest sites, filtered down to breath sound alone, and shown as a waveform and a spectrogram you can see and hear.

Get notified at launch See how it works
30 seconds per site Five standardized chest sites
Nothing leaves your phone No account, no cloud processing
A clinician's idea From an infectious disease physician
BreathPrint Select Site screen with all five chest sites recorded on a torso diagram and a 5 of 5 progress list BreathPrint tracheal analysis screen showing quality score, inhale and exhale segments, isolated breath sound, and spectrogram

Three Steps to Your Own Baseline

No account, no cloud processing. Everything happens on your phone.

  1. Record

    Hold your phone to five chest sites for 30 seconds each: tracheal, left and right upper, left and right lower. The app guides you through every site.

    BreathPrint Tracheal Recording screen with a 30-second timer, recording tips, and a Start Recording button

  2. Save your baseline

    On a day you feel well, save one full five-site set as your baseline. Breath sounds differ from person to person, so your own normal is a better reference than a population average.

    BreathPrint Bundle screen showing a sample recording with a Set as Baseline option and the tracheal recording listed by site

  3. See and hear your breathing

    BreathPrint filters out your heartbeat and shows the breath sound as a waveform and a spectrogram, with playback. Comparing a new recording side by side with your baseline is planned for a future version.

    BreathPrint analysis screen showing a quality score, inhale and exhale segments, the isolated breath sound waveform, a spectrogram, and the heart band for reference

What Happens to Your Recording

Every step happens on your iPhone. Your recordings are never uploaded.

  1. Capture

    You hold your phone to each chest site for 30 seconds.

  2. Separate

    The app filters out your heartbeat so only the breath sound is left. The heartbeat is kept for reference.

  3. Segment

    Each breath is split into inhale and exhale, and the app checks how clean the recording is.

  4. Visualize

    The breath sound is drawn as a waveform and a spectrogram, a picture of which pitches are in the sound over time.

  5. Save

    The five site recordings are saved together as one labeled baseline set.

Technical details
Audio format
AAC (.m4a), 44.1 kHz, mono
Heart and breath separation
Three cascaded RC filters
Spectrogram
Hann-window FFT with Apple's Accelerate framework (vDSP)
Testing
Filtering and spectrogram checked against known test signals before use on real recordings. Not clinically validated.
Built with
Swift, SwiftUI, AVFoundation, Accelerate/vDSP
Stage
Working iOS prototype

A Video Call Can't Hear What a Stethoscope Does.

During COVID, many patients were treated entirely through video calls, where a clinician could not place a stethoscope on their chest. Breathing problems went undiagnosed because that signal never made it through the call.

An infectious disease physician's clinical experience of missed diagnoses during this time motivated the idea behind BreathPrint.

Source: Remote Auscultation of Heart and Lungs as an Acceptable Alternative to Legacy Measures in Quarantined COVID-19 Patients. Peer-reviewed, PMC9103963.

BreathPrint was selected for SAIF 2026 in the Biotechnology & Digital Health track.

In the clinic

A stethoscope on the chest.

The clinician hears the breath sounds

On a video call

Camera and voice only.

Breath sounds never reach the clinician

With BreathPrint

The phone records five chest sites at home.

Breath sounds are captured and kept as your own baseline

Questions

Is BreathPrint a medical device?
No. BreathPrint doesn't diagnose anything. It records, filters and visualizes your breath sounds and keeps them as your personal baseline. Diagnosis remains the responsibility of a licensed clinician.
Do I need any extra equipment?
No. BreathPrint uses your iPhone's built-in microphone.
How long does a recording take?
30 seconds at each of five chest sites: tracheal, left and right upper, left and right lower.
Can it compare a new recording with my baseline?
Not yet. Side-by-side comparison with your baseline is planned for a future version. Today the app records, filters, visualizes and saves your recordings.
Where are my recordings stored?
Only on your phone. There's no account, server, cloud sync, or analytics. Deleting a recording removes it permanently.
When can I get it?
BreathPrint is a working iOS prototype and isn't on the App Store yet. Join the launch list and we'll email you once when it's available.

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