Mellow

Overview

Mellow is an Apple Watch app for people with epilepsy. It uses the watch’s sensors to detect seizures and alerts an emergency contact the moment one is detected. An iPhone companion app holds the seizure diary, emergency contacts and long-term stats.

My role

I built the iPhone and Apple Watch apps as part of a team of iOS developers, designers, backend and ML engineers.

Hardest part

Seizure detection only helps if it is always on, and “always on” is exactly what a watch is worst at. Monitoring has to run continuously in the background without flattening the battery before the end of the day, and the alert has to reach an emergency contact even when the phone is in another room.

We kept detection running on the watch itself so it never depended on the phone being nearby, and routed alerts through the backend so an emergency contact was notified independently of the paired device.

Architecture & stack

Swift and SwiftUI across iPhone and Apple Watch, with the watch app reading motion and heart-rate sensors and a CoreML model classifying seizure events, and push notifications delivering emergency alerts. HealthKit for health events logging.

Achievements

• Shipped a health-critical app on both iPhone and Apple Watch