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Cadence: A Sleep Tracker With No Subscription, Ever — image 1
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BUSINESS

Cadence: A Sleep Tracker With No Subscription, Ever

JW

Julian Weiss

Organizer

€28,500.00 raised of €75,000.00

38% 190 donors 30 days left
Every major sleep tracker now charges a monthly fee to see data its own sensor collected from your own body while you slept in your own bed. Several have added the fee after people already bought the hardware. Cadence is a sleep tracker that does not do this and structurally cannot. It is a small sensor that sits under the mattress — nothing worn, nothing charged nightly — measuring heart rate, respiration, movement and bed presence through ballistocardiography. It syncs to a phone app over Bluetooth. There is no cloud account, because the data never leaves your phone unless you choose to export it. We are a team of four, two of us from a medical devices background. The firmware and the app will be open source at launch under a permissive licence, and the hardware schematics are published. If we go out of business, your device keeps working and someone else can build for it. That commitment is structural, not a promise. Validation: we ran 140 nights against clinical polysomnography with a sleep lab in Zurich. Sleep-stage agreement was 79%, which we will state plainly is good for a consumer device and is not a diagnostic instrument. The full report is on our page including the nights it did badly. 75,000 EUR funds the production run of 2,000 units, certification, and the injection mould. Backing tiers: 150 EUR for one unit. 250 EUR for two, for a shared bed — the sensor separates sleepers. 450 EUR for the developer tier: a unit, the debug header, and direct access to our firmware team.
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Updates (2)

The firmware repository is live and public today, under Apache 2.0, rather than at launch as originally promised. Several of you said you would not back until you could read it. That was a fair position and it was easier to just publish it.

The polysomnography comparison is now public in full, including the raw per-night data. Night 62 is the one to look at if you want to see the device do badly — a restless-legs participant, and we handled it poorly.

Recent Donors (190)

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Agron Mehmeti19d ago

€236.84

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Emilia Çela20d ago

€120.00

Will there be a second run if this one sells out?

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Drilona Larsen20d ago

€25.00

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Claire Moreau20d ago

€900.00

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Chiara Rama20d ago

€250.00

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Armando Sula20d ago

€120.00

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Silvana Rroku20d ago

€25.00

Any chance spare parts will be sold separately?

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Tomas Rama20d ago

€45.00

Paguar me kënaqësi. Suksese!

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Hugo Dubois20d ago

€120.00

Will there be a second run if this one sells out?

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Rozeta Ndoja20d ago

€25.00

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Armando Sula21d ago

€120.00

Backed. Rooting for you.

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Chiara Rama21d ago

€45.00

Count me in.

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Genti Brahimi21d ago

€250.00

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Kreshnik Aliaj21d ago

€60.00

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Besnik Van Dijk21d ago

€25.00

Not much, but every bit counts.

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Claire Petrov21d ago

€199.00

Backed on the strength of the updates alone.

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Rudina Frashëri21d ago

€89.00

Hope this gets over the line.

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Gëzim Dubois21d ago

€60.00

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Redi Progni21d ago

€25.00

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Oliver Veseli21d ago

€900.00

Suksese!

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