Questions, answered.
Straight answers about what Klyft is, what's live today — face scan, peptides, the Correlation Engine — and how it works with the devices you already own.
What is Klyft?
Klyft is a longevity app for iPhone that brings your recovery, sleep, nutrition and protocols into one daily picture of your healthspan, with a deterministic Arc Score grounded in 800+ peer-reviewed studies. Live today: a 30-second face scan that reads 30+ wellness vitals from your front camera, peptide protocol tracking, and a Correlation Engine that shows what actually moves your numbers. It also reads any major wearable. Bloodwork analysis, supplement tracking and biological-age estimation are in active development.
What is Klyft's face scan?
30 seconds, 30+ vitals, just your phone. Hold your iPhone up, look at the front camera for half a minute, and Klyft returns a full vitals panel — heart rate, HRV, respiration, blood oxygen, blood pressure and more. No cuff, no strap, no ring, no extra hardware. It's live today, and it feeds straight into your Arc Score and the Correlation Engine. These are wellness estimates from a camera signal, not diagnostic measurements — Klyft is not a medical device.
How does the face scan work?
It uses rPPG — remote photoplethysmography. Every heartbeat pushes blood through your face and shifts the colour of your skin by an amount far too small to see. The front camera picks up those micro colour changes, and Klyft turns that signal into vitals. Decent light and a still 30 seconds are all it asks for.
What vitals does the face scan measure?
A sample of the 30+ it returns: heart rate, HRV (RMSSD and SDNN), respiration rate, blood oxygen (SpO2), blood pressure (systolic and diastolic), pulse-respiration quotient, stress index, sympathetic (SNS) activity, parasympathetic (PNS) activity, cardiac workload, vascular capacity, haemoglobin, autonomic balance and an overall wellness score. Every one of them is a wellness estimate, not a diagnostic measurement.
How accurate is the face scan?
Honest answer: it produces wellness estimates from a camera signal. That makes it useful for trends and day-to-day comparison — how you read this morning against your own last thirty mornings — and not for diagnosis. Klyft is not a medical device. For any clinical decision, a cuff or a wearable remains the reference, and your clinician makes the call.
Do I need a wearable to use the face scan?
No. An iPhone is enough. The face scan is the one measurement in Klyft that needs no hardware at all — no ring, no band, no chest strap, no cuff. Connect a wearable if you already own one and your sleep and recovery reads get sharper, but the scan stands on its own.
How is Klyft different from a wearable app like WHOOP or Oura?
WHOOP and Oura are tied to their own hardware (a band and a ring) and focus mainly on recovery and sleep. Klyft is device-agnostic — it reads the wearable you already own, and its 30-second face scan needs no wearable at all — and frames everything around longevity as a whole: recovery, sleep, nutrition, daily readiness and the protocols you run (peptides, with dose, timing and cycles). It also tracks peptide protocols and runs a live Correlation Engine across everything you log, which most wearable apps do not.
Do I need to buy hardware to use Klyft?
No. Klyft is an app and works with the wearable you already have — Apple Watch, Garmin, WHOOP, Oura, Fitbit or Polar. The face scan needs nothing but your iPhone. There's no Klyft ring or band to buy.
What if I don't have a wearable?
You can still use Klyft. The 30-second face scan, your iPhone's Health data, meal photos and protocol logging already power your daily Arc Score on their own — and you can connect a wearable like an Apple Watch, Oura or WHOOP any time to sharpen your sleep and recovery reads.
Does Klyft track peptides?
Yes — peptide tracking is live today. Log peptides with dose, route, timing and cycles in seconds, get reminders before each window, track honest adherence, manage on/off cycles, and export a clean history for your clinician. Klyft is a wellness tool, not medical advice.
What is the Correlation Engine?
It's live today, and it's there to show you what actually moves your numbers. The Correlation Engine weighs every input you log — peptides, training, sleep, food, face scans — against every metric Klyft tracks, and surfaces the relationships that hold up. Each one comes with an effect size, the window it was observed over, and a confidence level. It reports correlation, labelled as correlation: what moves with what, not what causes what. The causal call stays with you and your clinician.
Does Klyft track supplements or read bloodwork?
No. Klyft does not track supplements or read bloodwork. What the app does today is what this site describes: a 30-second face scan reading 30+ vitals, peptide and protocol tracking, sleep and recovery from any major wearable, photo meal logging, the daily Arc Score, the Correlation Engine and Ask Klyft.
What is the Arc Score?
The Arc Score is Klyft's single daily readiness number from 0 to 100. It combines your sleep, recovery, face-scan vitals and training load into one score with a plain-language call on how hard to push that day. It's computed by deterministic algorithms grounded in 800+ peer-reviewed studies — never generated by a language model. See the science.
Which wearables does Klyft work with?
Klyft reads from Apple Watch / Apple Health, Garmin, WHOOP, Oura, Fitbit and Polar, and you can connect several at once for one unified view of your sleep, recovery and vitals. You can also run Klyft with no wearable at all and rely on the face scan.
How much does Klyft cost?
Klyft offers a 7-day free trial, then $19.99 per month. There's no hardware to buy.
Is Klyft available on Android?
Klyft is currently available on iOS (iPhone), with a free trial on the App Store.
Is Klyft medical advice?
No. Klyft is a wellness tool built for healthy adults and does not provide medical advice, diagnosis or treatment. It is not a medical device, and the face scan returns wellness estimates rather than clinical measurements. Always consult a qualified clinician before starting or changing any supplement, peptide or other protocol.
Still curious? Try it.
Connect the wearable you already own — or just your phone — and start with a 7-day free trial.
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