Features & Capabilities

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.

User Growth & Download Statistics

App
By:
Nix, Inc.
Rating:
4.60
(30)
0.10
Version:
3.40 Last updated: 2026-06-03
Version code:
886455426
Creation date:
2022-11-22
Compatible devices:
Size:
62.59MB
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-06-07
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
Nix, Inc.
Apple Apps Store
https://apps.apple.com/us/app/nix-solo/id1632680170
Website:
https://nixbiosensors.com/

User Reviews

I’ve been using nix for the past 6 weeks and am blown away by the insights. I haven’t had any app crashes or bugs that I’ve seen on the other reviews. I have used whoop, garmin, levels, 8sleep, aura etc and this interface and usability is on par, or much better in some cases (garmin connect). I’m not currently training for a race, but this tool has almost given me a reason to sign up for another. Living on the lake outside of Houston, the Nix index is 100 on most of my workouts and I sweat considerably more than I would have ever imagined. Like 54oz doing yard work is nuts. Also, the breakdowns of how much of each electrolyte is very insightful and helpful in determining which drink and how much to consume before, during and after. I love this product and really glad it exists. I’m surprised it’s not a bigger deal than it is already.
by Au*****, 2025-07-10

The app was working fine. Now that it asked for update it won’t recognize my password or email. I have tried resetting my password and app to no avail.
by Hu*****, 2025-06-15

App crashed via Bluetooth connectivity during a 98°F ultra marathon yesterday so I couldn’t add fluid replenishment throughout the day; and it wouldn’t save my workout or reconnect to the Nix pod until I restarted my phone. I was at least able to retrieve sweat loss data after my run, but it added five hours of runtime (15.5 hours instead of what should’ve been 10.5, because the app wouldn’t let me save the workout until hours after). I would love to be able to edit the workout time, but that’s not an option. Also, regarding editing, I’ve tried to edit fluid replenishment and workout name, but it never saves the new edited data. Sharable graphics still isn’t working as well. Please work out these bugs because this is such a great tool when it’s working properly! Love being able to track my sweat loss; it really makes a difference in recovery after ultra marathons.
by Ma*****, 2024-09-01
View all user reviews ›

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