Iaso uses your phone's front camera to monitor your blood pressure, heart rate, heart-rate variability and breathing rate, with no cuff, no wearable and nothing to charge.
Iaso is not a medical device.
A scan takes thirty seconds and needs nothing but the phone in your hand.
Face a window or a lamp so the light falls on your face, and hold the phone where you can see yourself on the screen.
Iaso reads tiny colour changes in the skin of your face as blood moves through it.
You get systolic and diastolic blood pressure, heart rate, heart-rate variability and breathing rate. If the signal was weak, the reading says so.
Every heartbeat pushes a little more blood into the skin of your face, and that blood absorbs some of the light that would otherwise bounce back. A phone camera can pick up the tiny change in colour this causes, even though your eyes can't. The technique is called remote photoplethysmography, or rPPG for short, which means measuring your pulse with light without touching you.
Light that reaches your face travels a little way into the skin, and the blood in the tiny vessels near the surface absorbs some of it before the rest bounces back. Each heartbeat fills those vessels a bit more, so slightly less light comes back. Green light shows the change best, because haemoglobin, the part of blood that carries oxygen, absorbs green strongly. The green light on the back of a smartwatch works the same way, and a face scan uses the light already in the room.
The scan finds your face in every frame and follows patches of skin where the pulse shows well, such as the forehead and cheeks. It leaves out your eyes, mouth and hair, because they move or carry no pulse. The change in a single pixel can be smaller than the smallest step the camera records, so the scan averages every pixel in a patch into one colour for each frame. Once that colour is taken, the frame itself is no longer needed.
The raw colour also shifts when the light changes or your head moves, and those changes are usually bigger than the pulse itself. A heartbeat repeats at a steady pace, so filters keep only the rhythms a heartbeat can have and set the rest aside. The scan runs for thirty seconds because a rhythm only becomes clear over many beats. Movement and dim light can still bury the pulse, and darker skin absorbs more light before it reaches the blood, which leaves a fainter signal, so soft, even light on your face always helps.
Counting the beats gives your heart rate, and the small differences in the time between them give your heart-rate variability. Breathing gently lifts and lowers the whole trace, which gives your breathing rate. Blood pressure is the hardest of the four, and the research on it is the newest. The timing and shape of each beat carry clues about your circulation, and a measurement model turns those clues into a reading. Calibrating with your own cuff teaches the model how your circulation behaves, and for anything that matters clinically, a cuff is still the reference.
Every scan gives you the same four readings, and each one is saved to your history.
118/76mmHg
You get systolic and diastolic, the top and bottom numbers of a blood pressure reading.
64bpm
It counts your pulse in beats per minute.
48ms
It shows how much the time between heartbeats changes from one beat to the next.
14/min
It counts how many breaths you take in a minute.
The signal and the values on this page are illustrative.
Look back over a week, a month or a year, and drag through your charts one value at a time. Every reading sits in one history, which you can narrow to a single source.
Trends
Blood pressure
Avg 119/77 · last week
Blood pressure chart. 7 readings, from 121/78 to 120/77. Systolic ranged 116 to 124.
62bpm
Resting, from scans
49ms
7-day average
14/min
Resting, from scans
Resting heart rate
Avg 62 bpm · last week
Resting heart rate chart. 7 readings, 62 to 62 bpm, ranging from 61 to 63.
Heart-rate variability
Avg 49 ms · last week
Heart-rate variability chart. 7 readings, 48 to 50 ms, ranging from 46 to 53.
Hover over or drag across a chart to read each value. The readings here are illustrative.
Calibrating against a cuff monitor teaches the model how your own circulation behaves, which brings your blood pressure readings noticeably closer to what your cuff shows.
Calibration is optional. Until you do it, scans use the general model.
There's nothing to sign up for, and your readings are stored in a database on your phone.
Camera frames are read as they arrive and then discarded, so no video or photo of your face is kept.
Health sync stays off until you turn it on.
Joining the waitlist on this page is separate from the app. It sends your name and email to Cardilog so we can tell you when Iaso launches.
Iaso syncs with Apple Health on iPhone and iPad, and with Health Connect on Android. Sync stays off until you turn it on.
Each scan's readings are written to your health app.
Readings from other sources join your Iaso history.
Text grows with the size you set for the rest of your phone.
Use Iaso in light or dark mode.
Iaso has full VoiceOver labels, including a spoken description of every chart.
The whole app is available in all three languages.
Iaso works on iPad as well as iPhone.
Join the waitlist and we'll email you when Iaso launches.
A camera reading is not a diagnosis. Iaso is not a medical device and does not tell you whether a reading is normal, high or low. For anything that matters clinically, check with a cuff monitor and talk to your clinician. Never change medication based on this app.
