A digital heart
on your sleeve

SamaWritten wellness band with always-on medical ID display

Your medical info, always visible when you can't speak. Wellness insights measured against your own baseline, not a population average β€” and a contact who can check in, without the Internet.

Always-on medical IDWorks in 2GPersonal baseline insights
Read the Research
Global Ecosystem

Every metric.
Every moment.

Display
Always-On Medical ID

Your name, conditions, meds, allergies, and emergency contact β€” entered by you, readable by anyone. No app, no passcode.

Display
Heart Rate

Continuous heart rate and resting heart rate, tracked against your own baseline β€” not a population average.

Display
HRV & Recovery

Heart rate variability as a recovery and readiness signal, in plain milliseconds. Know when to push and when to rest.

Display
Sleep & Respiration

Four-stage sleep and overnight respiratory rate as a recovery insight. Wake up knowing how you slept.

Display
Check-In Alerts

A hard impact prompts the band to ask if you're okay. 30 seconds to respond, then your chosen contact is notified over 2G.

Five modalities.
One 2.82mm chip.

PPG Multi-channel optical - 530-940nm
Optical Sensing (PPG)

Heart rate - resting HR - HRV - respiratory rate

ECG 250Hz - Lead I equivalent
Single-Lead ECG

Heart rate + HRV capture - 30-sec on-demand

BIOZ 50kHz - 120dB SNR - <1uA
Bioimpedance

Body composition - general fitness insight

TMP TMP117 Β· +/-0.1C sensor
Skin Temperature

Skin-temperature trend - circadian baseline

IMU BMI270 - impact + motion
6-Axis IMU

Impact events - 4-stage sleep - activity

Looking at data over the long-term… [we can] dial it in to the individual patients in their individual lives and give people the best overall prediction of risk.
β€” Dr Joe Jensen, MD (Minneapolis Heart Institute Foundation)

Context for Every Bystander

Every 90 seconds, an American suffers an out-of-hospital cardiac arrest.

7 in 10 happen at home, unwitnessed.

<1 in 10 people survive.

CPR within 2 mins gives an 81% higher chance of survival.

After the next 10 golden minutes, it makes no difference.

SamaWritten shows your medical information and lets a contact check in, helping every Good Samaritan.

Supported by

What makes SamaWritten different?

SamaWritten vs typical wearables
SamaWritten
Always-on ID. Reaches your contact on its own.
Typical wearable
Great for runs. Quiet in emergencies.
Sensors
Five sensors reading heart rate, movement, and temperature all day.
One optical sensor counting steps and the odd heart rate.
2G
Reaches your chosen contact on its own. No Bluetooth, no Wi-Fi.
Useless the moment its host device is dead, charging, or out of range.
Check-ins
Notifies your loved ones, draws attention nearby with a high-pitch buzzer and blinking flash, and shows your medical ID instantly.
Buzzes on your wrist and alerts limited contacts with no other information.
Usability
A stranger can read your name, meds and emergency contact in seconds.
Locked behind a passcode and an app you have to know how to open.
Equity
Researched on darker skin tones β€” Monk 4–10, not as an afterthought.
Calibrated on light skin. Misreads SpOβ‚‚ on the people most at risk.

The physics is public.
The method is ours.

Three patent-track claims β€” two method, one apparatus β€” sit under every number on this page. We can't show you the maths yet. We can show you what it does.

Method 01 Β· Signal equity

Sensing that survives melanin.

Pulse oximetry famously degrades on darker skin β€” a documented, decade-old disparity. Our proprietary signal-recovery method recovers the optical signal melanin attenuates β€” equity from mathematics, not from averaging it away. Under study in our precursor research device.

Method 02 Β· Research sensing

New answers to old sensing problems.

Our cross-sensor fusion method attacks a measurement problem that has blocked non-invasive sensing for decades. It is under study in our precursor research device β€” research work, not a feature of any product for sale.

Apparatus Β· Single-site sensing

Two kinds of physics. One square centimetre.

A custom sensor board of our own design co-locates optical and electrical sensing at a single site on the wrist β€” so both methods above read the same pulse, on the same beat, from the same tissue.

Method and apparatus claims in preparation. Implementation details withheld pending filing.

Trusted by leading doctors, experts, and paramedics:

Trusted by leading doctors, experts, and paramedics. From cardiology to paediatrics, OB/GYN to blood banks β€” the clinicians who triage emergencies told us what they need.

Often the patient party arrives in a rush without proper history. This gives us the exact data we need, though adding a feature for direct lab system uploads down the line is required.

Honestly, I haven't seen anything quite like this in the market for at-risk patients.

In pediatric emergencies, the parents usually panic and can't give proper history. Having something that simply shows vitals is very important.

In city traffic, you lose time fast. A band like this is good for patients and their families, and there is really nothing else out there doing exactly this.

Getting ECG and PPG readings so easily is very helpful, though it would be great if it could eventually sync directly to our ward monitors.

Continuous, non-invasive cardiac readings at the bedside would genuinely help the children we monitor.

We get so many requests for blood every single day, specially for anemia cases, and it gets very busy. This tech is really important because it takes just seconds to read.

Adolescent and young women, especially following pregnancy, face huge burden of anaemia. The SamaClip helps in such situations β€” especially in remote areas, and in emergencies in remote patient care.

Your story on your wrist, always within reach.

↻
How it works
Sensing, insights, and check-ins, end to end.
Tap to flip β†’
How it works
  • Five on-wrist sensors fuse PPG, ECG, BioZ, EDA/GSR, and a 6-axis IMU into a continuous physiological stream.
  • On-device processing on a 2.82 mm chip learns your personal baseline β€” and notices when your numbers drift from your usual.
  • After a hard impact with no response, the band reaches out over 2G: your chosen contact gets a check-in notification with your location.
Read full
✦
The science
Our research program and evidence.
Tap to flip β†’
The science
  • Our precursor research device was studied with 182 participants against an accredited reference lab.
  • Results describe research performance of that precursor device only β€” never the performance of a product for sale. Full detail on the evidence page.
  • Skin-tone equity: the study deliberately recruited across all Monk Skin Tone categories, including Monk 8–10 where most commercial pulse oximeters have documented failures.
Read full
β™‘
What it tracks
Wellness today, research tomorrow.
Tap to flip β†’
What it tracks
  • Wellness metrics tracked continuously: heart rate, resting HR, HRV as recovery, respiratory rate in sleep, activity, sleep stages, skin-temperature trend.
  • Safety features: always-on medical ID you fill in yourself, fall/impact check-ins, caregiver notifications.
  • Research roadmap: our precursor-device program explores what continuous sensing may one day make possible.
Read full
β–£
Clinical trials
Open studies, cohorts, and ongoing research.
Tap to flip β†’
Clinical trials
  • Indiana research study β€” now enrolling residents aged 50+ for a 90-day observational study.
  • Compares our research device's signals against reference diagnostics across screening, onboarding, active wear, and follow-up phases.
  • Apply to participate or read the eligibility criteria in full.
Read full
β†’
Why this matters
The care gap, and what changes at scale.
Tap to flip β†’
Why this matters
  • The hardest constraint in wearables isn't the sensors β€” it's the $300 price floor that excludes the bottom 70% of the people who need one.
  • The worst moments happen when no one is watching: at home, at night, in transit. A wearable that only counts steps isn't enough β€” it has to speak for you.
  • Built for everyone the wearable industry priced out and miscalibrated for.
Read full
✱
Our story
Principles, constraints, and the mission.
Tap to flip β†’
Our story
  • Started by founders who watched family members wait too long for cardiac help β€” and who had access to better engineering than the people who needed it most.
  • Every architectural choice β€” e-ink display, sub-$10 BOM, on-device inference β€” falls out of refusing to design above the $300 line.
  • The product we'd want available to our own families: bystander-readable, accurate on every skin tone, priced for everyone.
Read full

Your story,
on your sleeve.

5 sensors. Always-on medical ID. 2G built in.
For the millions of people whose hearts need a guardian that never sleeps.

Talk to us β†’
$199 for SamaWritten Β· +$49 for SamaClip (institutions only, by agreement)