Zx: Heart Rate Zones Training Reviews

Zx Reviews

Published by on 2026-01-10

🏷️ About: Zx is your personal heart rate coach designed to guide you through your interval training. Create your own interval workouts or download workouts created by the community.


       


Is Zx Safe to Use?

We Investigate the app owner's website (Oversphere.net), verify their legitimacy, and uncover hidden scams and complaints.


Overall Customer Experience 😎


🤬 Negative experience
99.9%

😎 Positive experience
0.1%

🫥 Neutral
0.0%

~ from Justuseapp.com NLP analysis of 70 combined software reviews.

Is Zx Safe?
Zx: Heart Rate Zones Training does not appear safe based on available data.
0.1/100

  Safety Analysis »»

Is Zx Legit?
Zx: Heart Rate Zones Training does not appear legitimate based on our analysis.
0.1/100



Read 12 Customer Service Reviews 😠💢

4.3 out of 5
Eh

I got Zx thinking it would give me realtime workout info on what zone I am in and for how many minutes. It’s just like all the other apps. you can only see what zone you are in at that exact moment. It’s not realtime info (the kind you can use to guide your workout

Rip off

I was looking for something to exactly what Zx should do, if it worked! But the studio (self-created) workouts don’t work! They don’t sync with your phone and when you open it on your watch it just spins.. waiting for you to start the workout (that does not appear) on your watch. Biggest waste of $15. I tried to contact support but my email was bounced back and the link from Zx Store leads to a page that says coming soon. I’m going to try to request a refund because this is so pointless. A shame because I would have gladly paid the $15 for something that worked as expected.

Custom and community workouts not showing on my watch

I’m not able to use the custom and community workouts after paying for Zx because they don’t show up on my watch. 😕

Support did not respond

I contacted support about the zone categories double the amount of time I worked out in each zone. I sent a screen shot showing that I worked out 6 minutes in the intensity zone according to my custom heart rate and it recorded over 12 minutes. I requested help and the answer was “crickets”…I’ve been totally ghosted.
I would have rated Zx a 4 star, otherwise.

Overrated

Zx does nothing special that the normal Apple Watch workout app does not do. It’s designed poorly, there are few glitches. Do not bother buying.

:(

App shut down when editing

Like this app

4 stars. Would give 5 stars if the colored bars in the workout graph also displayed the target heart rate zones like the Polar Beat app. does.

Fantastic app!

I was looking for an interval timer for my own HIIT training that could also pair with my coros armband to show my heart rate.

Paying $14 for Zx seemed like a no-brainer when the cheapest watch I could find to show my heart rate was $180. Now I get to see my interval timer and heart rate in the one place. It works perfectly with my coros armband and make sure I stay in the zone during night intensity intervals (while not pushing too hard above my range). Thanks for making such an intuitive and affordable app with great functionality.

Awesome app!

I’ve been waiting for something like this. The ability to make my own workouts is something missing from other zone trainer apps I’ve used. The watch interface is slick and gives me everything I need. Plus the ability to download other users creations is great when I need inspiration. Support is great with fast communication when I had a question. Definitely looking forward to seeing how Zx evolves!

Watch complication of Z Score please

Watch complication of Z Score please

The this app score on the watch doesn’t match with the fitness level. For example, if I change to level 1, the iPhone app seems to be always at level 3. Please fix, thank you.

Resting Heart Rate has improved

Been using Zx now for a couple months and my resting heart rate has gone down by quite a bit. My doctor was impressed!!!

Apps doesn’t work right

It worked at first but no longer sync with Apple Watch



Is Zx Safe? 🙏

Zx: Heart Rate Zones Training does not appear safe based on available data. JustUseApp Safety Score for Zx is 0.1/100.
This assessment is based on our NLP analysis of 70 user reviews. Combined with the app store average rating of 4.3/5.

Safety Analysis

65.6% of users say app is safe 👍
65.6%

20.3% of users have some concerns ⚠️
20.3%

14.1% of users say app is risky 🚨
14.1%


Is Zx Legit? 💯

Zx: Heart Rate Zones Training does not appear legitimate based on our analysis. Our NLP models processed user feedback to estimate legitimacy. JustUseApp Legitimacy Score for Zx is 0.1/100 .
This conclusion is based on analysis of 70 user reviews.

🔏 Privacy & Data Safety

Zx collected the following data from you:

  • Data Linked to You:
    • User Content
  • Data Not Linked to You:
    • Identifiers
    • Usage Data
    • Diagnostics

Payments 💸

**Pricing data is based on average subscription prices reported by Justuseapp.com users..

Pricing Plans Amount (USD)
Premium Lifetime Access $14.99
Premium Monthly $0.99
Premium Monthly $2.99
Premium 6 months $7.99
Premium 6 months $9.99
Premium Yearly $24.99




How was your experience with Zx: Heart Rate Zones Training? Post a Review




Features

Zx is designed to push you to your maximum heart rate; while there shouldn’t be cause for concern with healthy individuals, always consult with your physician prior to starting any training regimen.

Subscription Terms: Your subscription automatically renews every month or year unless auto-renewal is turned off at least 24 hours before the end of the current subscription.

Any unused part or time-span of a free trial period will be forfeited, as soon as you purchase a subscription.

Your account will be charged for a renewed subscription within 24 hours prior to the end of current subscription.

You can manage your subscription and switch off the auto-renewal by accessing your iTunes account settings after purchase.

  Contact Support
Developer:
OverSphere LLC

Contact e-Mail:

Website: