HIYD Health Tracker: Add Health Tracking to the Watch You Already Wear

Last updated: 13 November 2026

What the HIYD health tracker is

HIYD is a slim disc, 2.7mm thick and 7 grams, that sits under your watch against your wrist. A nano-suction surface holds it on the caseback, with no magnets and no glue, and HIYD says it leaves no marks. So the watch on your wrist looks exactly as it did before.

The idea is health tracking you don't have to think about. You keep wearing the watch you like, and the sensor sends your data to the HIYD Health app on your phone. The founder, Salah Batroukh, spent about seven years as a manufacturing design engineer at Apple, according to TechCrunch.

What HIYD tracks

• Heart: heart rate, resting heart rate and heart rate variability.
• Breathing and temperature: blood oxygen, breathing rate and skin temperature.
• Sleep: a sleep score and sleep stages.
• Recovery: a daily readiness score that tells you whether to push or recover.
• Activity: steps, activity and VO2 max, an estimate of your aerobic fitness.
• Logging: cycle tracking and nutrition logging in the app.

HIYD key facts

• Size: 2.7mm thick and 7 grams, about the thickness of a £1 coin.
• Battery: four days, or up to 20 days with the optional Battery Band.
• Water: waterproof, and HIYD says you can wear it in the pool.
• Screen: none, and no notifications.
• Fit: 95% of watches, according to HIYD, with a 30-day fit guarantee.
• Phones: iPhone and Android.
• Syncs with: Apple Health, Google Health and Strava.
• Subscription: none for Kickstarter backers, who get the app free for life.
• Finish: black aluminium included; silver and gold cost extra.
• Price: not announced yet.

Will HIYD fit your watch?

HIYD says the sensor fits round, square, rectangular and asymmetrical cases, women's and unisex models, and watches on NATO straps. If your watch has an engraved or raised caseback, there's an optional Caseback Adapter, and there's a NATO Adapter too. Every Kickstarter sensor also comes with a free Soft Band in Onyx, Dune, Sage or Petal, for the gym, the pool and sleep.

The box holds the sensor, the Soft Band and a charger, and the app is a free download. The Battery Band, which takes battery life to 20 days, is an add-on in the same four colours.

The HIYD app, your data and the AI coach

The HIYD Health app shows how you slept, how recovered you are and one suggestion for the day. HIYD says your data is encrypted and never sold. The app also includes Coach HIYD, an optional AI assistant that explains your data. It runs on an existing third-party AI model, uses only data from your own HIYD, and you can switch it off at any time.

I couldn't find whether the sensor can keep your data on your phone without a HIYD account, so check the campaign page or ask HIYD before you back it if that matters to you.

HIYD Kickstarter status

The campaign hasn't launched yet. The Kickstarter page shows "Launching soon", and TechCrunch reported a November 2026 launch, with more than 16,000 people already paying deposits for the first units. Click "Notify me on launch" on Kickstarter to unlock up to 33% off when it goes live.

Backing a Kickstarter isn't the same as buying from a shop. Kickstarter's trust page says projects are not finished products, and that neither Kickstarter nor the creator guarantees you'll receive your reward or a refund.

Follow HIYD on Kickstarter

If you'd rather have a screenless band that's already on sale, my Fitbit Air page covers Google's at £84.99.

HIYD health tracker FAQs

How much does HIYD cost?

HIYD hasn't announced a price yet. It will be set when the Kickstarter campaign launches, and signing up for launch alerts unlocks up to 33% off. I checked the campaign page on 28 October 2026.

When can I get HIYD?

HIYD is launching on Kickstarter first, and TechCrunch reported a November 2026 launch. Delivery dates will depend on the campaign.

Does HIYD work with Apple Health?

Yes. HIYD says its app syncs with Apple Health, Google Health and Strava, on iPhone and Android.

How long does the HIYD battery last?

Four days on the sensor alone, or up to 20 days with the optional Battery Band.

Does HIYD need a subscription?

Not for Kickstarter backers, who get the app free for life. HIYD hasn't said what later buyers will pay.

Will HIYD damage my watch?

HIYD says the nano-suction surface leaves no marks, and it uses no magnets or glue. TechCrunch reports it comes off with a little prying.

Does HIYD have a screen?

No. There's no screen and no notifications, so you check your data in the app.

HIYD is a Kickstarter project that hasn't launched yet. Prices, features and delivery dates can change, and backing a project carries the risk that it doesn't deliver. This page is general information, not health advice.

More from CoolCuration

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• Christopher Ward C60 Pool Diver: a British automatic dive watch to wear a HIYD under.
• Google Pixel Watch 4 review: if you decide you want a smartwatch with a screen after all.
• Gifts for life: things built to last for years, not one product cycle.
• Back Market: sell your old smartwatch, or buy refurbished tech.

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