Most health wearables follow the same playbook: sell hardware at cost, lock the data behind a monthly subscription. Oura charges $6/month. Whoop charges $30/month. Even Samsung and Apple gate advanced health metrics behind premium tiers.
We are building Adola Ring to break that pattern. One purchase, all your data, no recurring fees.
The Hardware
Adola Ring packs six sensors into a titanium form factor under 3 grams:
- PPG (Photoplethysmography) -- Dual-wavelength green + infrared LEDs for continuous heart rate, HRV, and SpO2 tracking
- Skin Temperature Thermistor -- 0.1C resolution NTC sensor for circadian rhythm and cycle tracking
- 3-Axis Accelerometer -- Low-power MEMS accelerometer for sleep staging, step counting, and gesture detection
- Electrodermal Activity (EDA) -- Micro-current skin conductance electrodes for stress response measurement
- Bioimpedance (BIA) -- Body composition estimation via multi-frequency impedance analysis
- Ambient Light Sensor -- Adaptive LED intensity and environmental light exposure logging
The MCU is an ultra-low-power ARM Cortex-M33 running at 64 MHz with a dedicated sensor hub coprocessor that handles continuous sampling while the main core sleeps. Target battery life is 7 days with all sensors active.
Privacy by Design
Every health metric is processed on-device first. Raw sensor data never leaves the ring unless the user explicitly exports it. The companion app stores data locally in an encrypted SQLite database. There is no cloud account requirement, no telemetry, no data brokering.
The firmware will be open-source after launch. Users can audit the entire data pipeline from sensor ADC to rendered chart.
Why This Architecture Matters
The standard wearable architecture offloads all processing to a phone app that phones home to a cloud backend. This creates three problems:
- Latency -- Real-time biofeedback requires on-device inference, not round-trip cloud calls
- Privacy -- Health data is among the most sensitive personal information; centralized storage creates a single breach target
- Vendor lock-in -- When the company sunsets the cloud service, the hardware becomes a paperweight
Adola Ring runs a lightweight inference engine on the Cortex-M33 for sleep staging and activity classification. The BLE stack streams processed metrics to the companion app, which does visualization and long-term storage locally.
The Stack
- Firmware: Zephyr RTOS, written in C with sensor drivers for each of the six sensors
- BLE Protocol: Custom GATT service with characteristic-per-metric design for efficient polling
- Companion App: React Native with local SQLite storage, no backend dependency
- Charging Dock: USB-C magnetic pogo-pin dock with alignment magnets
Current Status
The ring is in late-stage prototyping. We are running validation on sensor accuracy against medical-grade reference devices and tuning the power management state machine to hit the 7-day battery target.
Early access is open now at adola.app for a $5 refundable deposit (total retail price will be $79.99). Early backers lock in the lowest price and get first-batch shipping priority.
What We Are Looking For
If you work on embedded health sensors, low-power BLE firmware, or privacy-preserving health data systems, we would like to hear from you. Drop a comment or reach out through the site.
Adola Ring: Own your health data. No subscriptions. No cloud dependency.
Top comments (0)