Phlex Swim platform, 2023 relaunch

The problem

Manufacturing our own tracker was the most expensive thing Phlex did and the thing customers cared about least. They wanted the data. In 2023 we relaunched as a software platform: a partner sensor for the heart-rate and motion capture, an Apple Watch app for everyone else, and a competition format to give the numbers somewhere to go.

What I did

I wrote the native Apple Watch app in Swift, ran the Polar partnership that made the Verity Sense our primary tracker, and led the Arena partnership that launched the Virtual Swim League. I also produced the relaunch content, including the explainer film on the Phlex films page.

How it fit together

The Verity Sense records to its own flash during the swim with no phone present; the app arms it before the session, collects the recording afterwards over Bluetooth, and uploads it for processing. The Apple Watch app gave the same lap and stroke reporting to swimmers who already owned a watch. Both fed one platform, and the Virtual Swim League ran on that data across remote pools.

// The watch session: one workout, one upload, no phone in the water.
let session = try HKWorkoutSession(healthStore: store, configuration: swimConfig)
session.startActivity(with: .now)
// ... laps accumulate from the built-in swim tracking ...
try await uploader.submit(workout: session.associatedWorkout, poolLength: pool.meters)

What shipped

• Native Apple Watch app
• Polar Verity Sense integration and offline-recording flow
• Improved stroke algorithm with secondary wrist tracking
• Virtual Swim League platform and the Arena launch campaign

Results

Hardware cost left the business. Tracking accuracy improved with a better sensor. The platform reached Apple Watch owners without a device purchase, and the league gave Arena a competition format nobody else had.