HelioCore

HelioCore is an open-source iOS and macOS app that lets you read health data directly from a Helio Smart Strap, a fitness wearable that belongs to the Zepp and Huami family of devices. The app is built in Swift and bypasses the official Zepp app and cloud dashboard entirely, streaming your biometric data straight to your Apple device over Bluetooth.

The way it works: you enter your Zepp or Huami account credentials into the app, which contacts the official Zepp API to fetch your account's authentication token and encryption key. The app then uses those credentials to connect to your Helio wearable over Bluetooth and perform the encrypted handshake the device expects. Once connected, it reads the raw data streams coming from the hardware and decodes them on the spot, displaying live readings for heart rate, heart rate variability, blood oxygen saturation, skin temperature, and stress level.

The project is built for people who want to own their biometric data rather than routing it through a proprietary cloud service. All credential handling and data processing happens on your Apple device and never leaves it beyond the initial authentication call to Zepp's own servers. The app does not collect or share any personal data.

The README is brief and does not include build instructions or an App Store link. It references two open-source projects that provided the Zepp authentication logic and Bluetooth protocol details used to build HelioCore. A valid Zepp or Huami account paired with a Helio device is required.