Amazfit Helio Strap Call Alerts Arrive via OpenStrap App

The Amazfit Helio Strap has always had a vibration motor, but Zepp’s own app only uses it for basics like pairing and low battery. An unofficial open-source Android app called OpenStrap now uses it to buzz for incoming calls and phone notifications. For Helio Strap owners who wanted a screenless tracker that still taps their wrist, it opens that up, at the cost of running a reverse-engineered app that its own developer has tested on a single phone.

What Happened

Gadgets & Wearables reports that OpenStrap talks to the strap directly over Bluetooth, after its developer reverse-engineered the tracker’s communication protocol. Beyond call and notification alerts, it can start workouts from the phone, show live heart-rate zones, use the phone’s GPS for outdoor sessions, and vibrate when the wearer leaves a target heart-rate zone.

OpenStrap’s GitHub page shows it is more than an alerts add-on. It is a full replacement for the Zepp app that keeps health data on the phone. It syncs sleep, heart rate, HRV, SpO₂, stress and workouts, calculates its own recovery and energy scores, and supports CSV export and Android Health Connect. It needs Android 9 or newer, is licensed under MIT or Apache-2.0, and says it is not affiliated with Zepp Health or Amazfit.

Why It Matters

Zepp Health hasn’t said publicly why it left phone notifications out. Gadgets & Wearables suggests two possible reasons, neither confirmed: battery life, since the strap’s 232 mAh battery is rated for up to 10 days of typical use, and positioning, since Zepp sells the Helio Strap as a passive health, recovery and training tracker rather than a smartwatch. OpenStrap shows the hardware can handle the alerts. What it doesn’t show is the battery cost.

The setup shows how unofficial this is. According to the README, owners link the strap in the Zepp app once using an email and password account, because Google or Apple sign-in won’t work. They then force-stop Zepp without unlinking the strap, since unlinking wipes the key, and pair it in OpenStrap. The README says to treat that key like a password. The first pairing still depends on Zepp’s server.

The data will also look different. OpenStrap uses its own model, so its scores won’t match Zepp’s, and recovery needs about a week of nights before it shows a score and around four weeks to settle. The README states plainly that it is “Not a medical device.” Its scores are estimates, not clinical readings.

What This Means for Screenless Tracker Owners

Notifications are becoming a dividing line among screenless bands. A reader comment on the Gadgets & Wearables article points to Garmin’s forum release notes for the Cirqa band, which added vibration for smart notifications and incoming calls in software version 4.20 on October 19. Google’s screenless Fitbit Air shows another way software shapes these devices: Stack Archive covered how its blood pressure and insulin trends sit behind Premium. With bands like these, what the software allows matters as much as the sensors.

Source: Gadgets & Wearables

Content created with AI assistance and reviewed for accuracy.