S1 Companion app for iPhone and iPad

Push the boundaries of your performance with the worlds most accurate hydration sensor.

The S1 gives you an unprecedented understanding of your body’s hydration needs for training and race-day. It measures your water and electrolyte losses in real-time, with an accuracy on par with in-field gold standards. The S1 is trusted by WorldTour Cycling teams and Olympic Gold medal triathletes.

The S1 Companion App gets the most out of your S1 device:
- Understand your sweat composition for a session, and view your hydration recovery plan.
- Study your previous sessions with our insights tool. We show your hydration problem areas and provide tailored recommendations on how to improve.
- You can connect all of your favourite fitness apps and devices including Garmin, Wahoo, Zwift and Coros - we’ve got you covered.