HeartCast vs Strapless HR

BeatCast is a pure software solution that broadcasts real-time heart rate from your Apple Watch to cycling computers via Bluetooth Low Energy (BLE) — no chest strap needed. Key Features: • Direct Mode: Apple Watch broadcasts BLE heart rate signal directly. Search for "heart-watch" on your bike computer to connect. • Bridge Mode: Watch sends heart rate to iPhone, which broadcasts BLE signal (device name "heart-phone") for broader bike computer compatibility. • Real-time Sync: Watch and iPhone stay in sync via WatchConnectivity. • 5 Heart Rate Zones: Based on the Karvonen HRR formula, with customizable age and resting HR. • Dynamic Island & Lock Screen: Live heart rate, zone name, and connection status at a glance. • Privacy First: All data processed locally on device. No data uploaded to any server. Fully compliant with privacy regulations. Perfect for: • Monitoring heart rate on your bike computer while cycling • Replacing a traditional chest strap with just your Apple Watch • Tracking heart rate zones during indoor training

Your Apple Watch already measures your heart rate. Your bike computer just can't see it. [App Name] fixes that. Your iPhone becomes a standard Bluetooth heart rate sensor and broadcasts the heart rate your Watch is measuring. Your head unit connects to it exactly the way it connects to a chest strap — because as far as it can tell, that's what it is. Leave the strap at home. HOW IT WORKS 1. Start a ride on your Apple Watch. 2. Your iPhone begins broadcasting as a Bluetooth heart rate sensor. 3. On your bike computer, open the sensor menu, add a heart rate sensor, and select the device that appears. Drop your iPhone in a jersey pocket and go. The screen can stay locked for the whole ride. BUILT TO BEHAVE LIKE A REAL SENSOR Getting a phone to impersonate a heart rate strap convincingly is the hard part. This app handles the details head units actually care about: • Implements the Bluetooth SIG Heart Rate Profile, so any head unit that accepts a BLE heart rate strap will work. • Streams at 1 Hz, the same cadence as a real strap, so your computer never reports the sensor as lost. • Carries a serial number that stays the same across launches, so your head unit recognises it as the same sensor ride after ride instead of asking you to pair again. • Keeps broadcasting in the background and while your iPhone is locked. • Re-advertises automatically when your head unit disconnects or powers down, so you never have to delete and re-add the sensor. • Keeps sending your heart rate through auto-pause, so your computer still reads a pulse while you wait at a light. A FULL RIDE COMPUTER ON YOUR WRIST The Watch app is more than a sensor. It records the ride: • Live, average and maximum heart rate • Five heart rate zones with time spent in each, based on your age from Health • Current speed, average speed and distance • Elevation • Active calories • Automatic splits every kilometre • Activity rings you can watch close in real time • A full summary when you finish Rides are saved to Apple Health as cycling workouts, with the GPS route included when location is enabled. SMART ENOUGH TO LEAVE ALONE • Auto-pause stops the timer when you stop and resumes when you roll again. • Put your Watch on the charger or take it off mid-ride and the ride ends and saves itself, instead of running all night. • Accidental rides that last only seconds are discarded rather than cluttering up Health. • Riding indoors? Turn GPS off to save battery. PRIVATE BY DESIGN No account. No sign-up. No server. No analytics. Your heart rate goes from your Watch to your iPhone to your bike computer over Bluetooth, and stops there. Nothing is uploaded, because there is nowhere to upload it to. The app works entirely offline. BEFORE YOU BUY • Works with bike computers that support Bluetooth (BLE) heart rate sensors. Pair from your computer's sensor menu, not from iOS Settings. • Bluetooth only. If your head unit is dual-band and defaults to ANT+, choose the Bluetooth sensor option. • An Apple Watch is required. iOS 26 and watchOS 26 or later.