Independent research on wearable health trackers, sleep tracking, and biometric sensors.
The original Basis Peak was Intel's bet on quantified self. It got recalled. The wearable industry kept moving. We pick up where Basis left off — testing the trackers, sleep rings, and recovery bands worth your time, and the ones that are quietly cloud-dependent traps.
Where we'd start
Our top picks across Fitbit, Garmin, Withings and Apple — with the trade-offs each brand quietly hopes you'll miss.
Intel pulled every Peak in 2016 after burns and blisters. Here's the timeline, the CPSC notice, and what it tells you about today's wearables.
Optical heart-rate, SpO2, sleep staging — what the peer-reviewed studies actually say versus the marketing copy.
Why trust BasisScience
We're a small editorial team that has used most of these wearables on our own wrists, fingers, and chests. Where we haven't, we say so. Our recommendations don't change because Amazon raises a commission rate, and we won't tell you a recalled device is fine.
- Independent — no manufacturer, retailer, or PR firm has any say in our coverage.
- We disclose when a link earns us a commission, and which products we have not personally tested.
- We update our buying guides with a visible "last updated" date and a public changelog.
- We publish a corrections policy and fix the record in public.
The Basis Peak archive
If you landed here looking for the original Basis Science site, the Peak, or the Basis B1: this is the part of the site for you. We've rebuilt the historical record from FDA filings, Intel press releases, CPSC notices, and archived support docs.
If you wanted a Basis Peak in 2026, here is what to buy instead. Five trackers ranked by how closely they match the original Peak's value proposition.
What the Basis Peak's continuous wrist-PPG actually measured well, where it broke, and how the November 2015 firmware update changed the optical sensor.
A retrospective on Intel's Basis Peak — the square OLED tank with four-day battery, laggy cold-weather touchscreen, and a HR sensor that quit at HIIT.
How the Basis Peak inferred sleep stages from heart rate, skin temperature, GSR, and motion in 2014, and how it stacks up against Oura, Whoop, and Fitbit today.
Modern alternatives
If you bought the Peak in 2014 you cared about: continuous heart rate, real sleep tracking, multi-day battery, a screen you could read in sunlight, and an app that wasn't going anywhere. Today's market answers that — unevenly.
Five fitness trackers we actually recommend in 2026, sorted by who they're for. Fitbit Charge 6 wins overall; Garmin, Apple, Withings, and Oura take the rest.
Four sleep trackers worth wearing in 2026, scored against peer-reviewed accuracy data. Subscription costs, real battery life, and what we ruled out.
Apple Watch SE 3 vs Fitbit Charge 6 compares an iPhone smartwatch with a slim Fitbit band for sleep, heart health, battery, privacy, and cost in 2026.
The best fitness tracker without subscription fees depends on battery, ECG, sleep, GPS, exports, and free app depth. These are the no-paywall picks.
How wearable health actually works
The sensors are simple, the marketing isn't. Plain-language explainers for the metrics that show up on your wrist.
A plain-language primer on N1, N2, N3 deep sleep, and REM: what happens in the body, what they're for, and how consumer wearables infer them without an EEG.
Wearable health data privacy is mostly governed by app terms, cloud accounts, exports, and state laws, not HIPAA. Here is what to check before you buy.
Wearable sleep score accuracy depends on sensors, fit, algorithms, and context. Here is why the trend can help when the exact number is wrong tonight.
What wrist-worn fitness trackers actually measure well, where they fall apart, and why calorie burn is still the worst number on the screen.
Explore every guide
The full editorial library, grouped by the decisions readers are usually trying to make.
Basis Peak archive
The recall, shutdown, product history, and what the Peak still teaches wearable buyers.
- Basis Peak Alternatives in 2026: Five Watches That Fill the Gap Basis Peak archive
- Basis Peak heart rate accuracy: what the sensor could and could not do Basis Peak archive
- Basis Peak review, eight years on: what wearing one actually felt like Basis Peak archive
- Basis Peak sleep tracking: a multi-signal design a decade early Basis Peak archive
- Basis Peak vs Fitbit Charge HR: the 2015 head-to-head, revisited Basis Peak archive
- Basis Peak: the complete archive of Intel's discontinued health watch Basis Peak archive
- Can you still use a Basis Peak in 2026? Basis Peak archive
- Intel's Basis Science acquisition: anatomy of a $100M+ wearables bet Basis Peak archive
- The Basis Peak recall: a timeline of what Intel knew and when Basis Peak archive
- Why the Basis Peak failed: a four-thread post-mortem Basis Peak archive
Modern wearable guides
Buying guides, reviews, and comparisons for current watches, bands, and rings.
- The best fitness trackers in 2026: five picks, honest trade-offs Modern wearable guides
- The best sleep trackers in 2026, ranked by what they actually measure Modern wearable guides
- Apple Watch SE 3 vs Fitbit Charge 6 for Sleep and Heart Modern wearable guides
- Best Fitness Trackers Without a Health Subscription Fee Modern wearable guides
- Best Sleep Trackers for Light and Restless Sleepers 2026 Modern wearable guides
- Best Smart Rings for Sleep in 2026: What We Recommend Now Modern wearable guides
- Fitbit Charge 6 vs Garmin Venu 3: Everyday Health Guide Modern wearable guides
- Oura Ring 4 vs Samsung Galaxy Ring: Which Should You Buy? Modern wearable guides
- Smart Ring vs Apple Watch for Sleep and Recovery in 2026 Modern wearable guides
- Apple Watch vs Fitbit for Health Tracking: Series 9 vs Charge 6 Modern wearable guides
- Best Fitness Trackers for Sleep in 2026: Bands That Track the Night Modern wearable guides
- Best Fitness Trackers Without a Subscription (2026) Modern wearable guides
- Best Smartwatch for Health Tracking in 2026: Five Honest Picks Modern wearable guides
- Fitbit Charge 6 review: a year on the wrist, with a chest strap Modern wearable guides
- Fitbit vs Garmin in 2026: two wearable philosophies, compared Modern wearable guides
- Garmin Vivosmart 5 Review: The Slim, No-Subscription Band Modern wearable guides
- Oura Ring Gen 3 vs Whoop 4.0: which screenless tracker is for you Modern wearable guides
- The Best Health Trackers in 2026: ECG, AFib, SpO2 and Skin Temp Modern wearable guides
- Withings ScanWatch 2 review: the analog watch that takes an ECG Modern wearable guides
Sensor and health explainers
Plain-language references for sleep, heart, temperature, SpO2, privacy, and sensor accuracy.
- Sleep stages explained: light, deep, REM, and what wearables guess Sensor and health explainers
- Who Owns Your Wearable Health Data From Rings and Watches Sensor and health explainers
- Why Your Wearable Sleep Score Can Often Be Wrong at Night Sensor and health explainers
- Fitness tracker accuracy: steps, distance, GPS, and calories tested Sensor and health explainers
- Resting Heart Rate, Explained: What the Number Actually Means Sensor and health explainers
- Skin temperature on wearables: what the number actually means Sensor and health explainers
- Smartwatch ECG explained: what the wrist reading can and cannot do Sensor and health explainers
- SpO2 on wearables, explained: what wrist oxygen readings actually mean Sensor and health explainers
- Wearable sensor accuracy: what your tracker really measures Sensor and health explainers
- What is HRV? A plain-language guide to heart rate variability Sensor and health explainers
- When the cloud goes dark: the structural risk in every wearable Sensor and health explainers
- Where Your Wearable Health Data Actually Goes (And Who Sees It) Sensor and health explainers