Ryan Rosenbaum
Projects

02Phlex Swim

2016 – 2024

I co-founded Phlex in 2016 and worked across every side of it. I ran the crowdfunding campaign, launched two products (the Phlex EDGE sensor, then the Phlex × Polar Verity Sense platform), managed partnerships with Polar and Arena, sold to teams and clubs, developed the iOS and Apple Watch apps, and worked with sports scientist Eva Piatrikova to ground the metrics in training research. I also made most of the films.

Calvyn Justus · Phlex EDGE
Role
Co-founder · Crowdfunding · Partnerships · Team sales · iOS & watchOS development · Creative direction
Collaborators
Phlex engineering team · sports scientist Eva Piatrikova · Polar · Arena · Innerbloom Film
Timeframe
2016 – Dec 2024
Outcome
Phlex 1.0 (EDGE) shipped after an Indiegogo campaign. Phlex 2.0 moved to software with Polar Verity Sense, a native Apple Watch app, team accounts, and the Arena Virtual Swimming League.

Challenge

Turn swim-tracking hardware and training data into something swimmers and coaches can use, then explain the product clearly enough to launch it.

My decisions

I built iOS and Apple Watch experiences as Phlex moved from its own EDGE hardware to the Polar Verity Sense platform.

I worked with Eva Piatrikova on training metrics, managed the Polar and Arena partnerships, and connected the product work to launch films and team onboarding.

Result

The work spans two product generations, shipped mobile and watch experiences, and the Arena Virtual Swimming League partnership. The product screens and campaign breakdowns below show the deliverables.

See the workApple Watch product ↗Arena partnership announcement ↗Public references checked September 25, 2026.

The Phlex platform

phlexswim.com
01

Track

Time, distance, technique, and heart rate for every swim.

02

Analyze

Personal training zones, set recognition, and stroke metrics.

03

Improve

Progress in technique, speed, and fitness, with training load over time.

04

Apple Watch

A native watchOS app: connect and jump in.

05

Polar Verity Sense

Head-worn heart rate for accuracy the wrist can’t match in water.

06

Phlex PRO

A web dashboard for coaches to follow a whole team.

07

Splash Score

Points for every swim, weighted by intensity, that power the league’s team standings.

Crowdfunding and Phlex EDGE

Phlex 1.0. EDGE was a goggle-mounted swim tracker with real-time heart rate and in-water haptic alerts. I ran the Indiegogo campaign that funded it: the strategy, the page, the launch film, and the athlete shoot with Olympian Calvyn Justus.

Phlex × Polar Verity Sense

Phlex 2.0. In 2023 Phlex moved from its own hardware to a software platform paired with the Polar Verity Sense heart-rate sensor. I developed the iOS app and the native Apple Watch app, so swimmers could train with a device they already owned.

Natalie Hinds · Phlex × Polar Verity SenseNatalie Hinds · Phlex × Polar Verity Sense
TrackTrack
AnalyzeAnalyze
ImproveImprove
Apple WatchApple Watch
Polar Verity SensePolar Verity Sense

Partnerships and team sales

I managed the partnerships that made 2.0 work: Polar on the hardware side, Arena on the league and its athlete ambassadors. In parallel I sold Phlex to teams and clubs, onboarding coaches onto Phlex PRO so they could follow a whole squad’s training from one dashboard.

Arena × PhlexArena × Phlex
Polar Verity SensePolar Verity Sense

Grounded in sports science

I worked with sports scientist Eva Piatrikova to define how Phlex measured effort: training zones, set recognition, stroke metrics, and training load. That work became the basis for the app’s analysis and, later, the league’s Splash Score.

With Eva Piatrikova on deckWith Eva Piatrikova on deck

Virtual Swimming League

A global, gamified swimming community inside the Phlex app. Swimmers join teams led by Olympic and world-class athletes who set workouts and keep them motivated, then log pool or open-water swims on an Apple Watch or Polar Verity Sense.

Every swim earns splash points based on intensity, feeding team scores and global leaderboards. Seasonal battles, levels, and prizes ran through partners including Arena, whose champions became league ambassadors for a three-month season.

Films and campaigns

Alongside the business, I directed, shot, and edited most of Phlex’s films: athlete stories with Calvyn Justus and Cody Miller, the launch teaser, and the product explainers. For the flagship “Every Breath Is Fuel” commercial I produced and cut the social edits while Innerbloom Film directed.

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