Nix Solo3.48 - App Store

To train at your peak, you can’t just train hard. You need to train in a way that’s informed by your personal biology.

The Nix Solo app allows users to monitor their own personal fluid and electrolyte losses in real time during a workout using the Nix Hydration Biosensor. This companion app provides valuable insight into their unique sweat composition and individual hydration needs based on their personal biology.

At Nix, we built the first biosensor to analyze sweat and provide endurance athletes with personal hydration data - scientifically validated, and delivered in real time.

Once paired with the Nix Hydration Biosensor, you are on your way to understanding your hydration needs with Nix Solo, our individual monitoring app. We’re the first hydration biosensor of its kind - the only pod, patch, and free app combination to:

- Evaluate the electrochemical biomarkers in your sweat
- Send real-time updates to your phone, Apple Watch, Garmin Watch, or Garmin Bike Computer
- Correlate your sweat data and your training environment with the Nix Index - a composite index of six environmental factors: temperature, humidity, dew point, altitude, wind speed, and solar load
- Provide post workout Sweat Intelligence via insights on your Sweat Profile including fluid loss rate, electrolyte loss rate and sweat composition metrics

Before your workout, tell the Nix Solo app what type of workout you’re doing and what you’ll be hydrating with. You can also consult the Nix Index to see how your environment impacts your hydration needs.

Once you start sweating, our single-use patch begins measuring and analyzing your fluid and electrolyte losses minute by minute- metrics that represent your unique “sweat composition.” This data is instantly streamed to our app, and can also be shared with devices like your Apple Watch, Garmin Watch, and Garmin bike computer.

The result is knowing when, what, and how much to drink in real time to enhance both safety and performance.

Version History - Minor bug fixes 3.48 Sep 24 - Minor bug fixes 3.47 Sep 19 - Minor bug fixes 3.46 Sep 9 - Minor bug fixes 3.45 Aug 27 - Minor bug fixes and performance improvements 3.44 Aug 9 - Minor bug fixes 3.42 Aug 6 - Minor bug fixes and performance improvements 3.41 Jun 18 - Minor bug fixes 3.40 Jun 3 - Minor bug fixes and performance improvements 3.39 Jun 2 - Minor bug fixes and performance improvements 3.38 May 20 - New loyalty feature
- Minor bug fixes and UI improvements 3.36 May 12 - Minor bug fixes 3.35 May 2 - Minor bug fixes 3.34 Apr 24 - Minor bug fixes 3.33 Apr 20 - New workout types
- Minor bug fixes and performance improvements 3.32 Apr 15 - Minor bug fixes 3.31 Mar 27 - Added support for French and Portuguese for in-app language selection. 3.30 Mar 20 - New Feature: Preferred Drink
- Minor bug fixes and performance improvements 3.29 Mar 11 - New Feature: In App language toggle (English and Spanish) 3.27 Feb 19 - Minor bug fixes 3.26 Feb 2 - Minor bug fixes and improvements 3.25 Jan 27 - Minor bug fixes and improvements 3.24 Jan 25 - Support for the Nix Solo Watch app has been restored
- Other minor bug fixes and improvements 3.23 Jan 24 - Updated the output of the recovery, predictive, race day and custom drink calculator
- New feature: Priming Calculator
- Minor bug fixes and performance improvements 3.21 10/29/2025 - Fixed an issue that was causing pod firmware update to fail intermittently 3.19 10/23/2025