Fourth FrontierReviews of fourthfrontier.com

This is a perfectly good HR monitor, and the ECG feature is definitely nice. But the other metrics, such as VO2 max and HRV are just laughable. IF you want those features, move on. If you want a HR & ECG tool, go for it. They have confirmed with me that the do not "measure" VO2 Max, or VO2 peak - they estimate it based on your personal data. I can literally increase or decrease my VO2 scores by changing my age within the app. That's pretty useless, since my actual Volume of O2 used did not change just because my age changed. Basically, except for the ECG feature, I can get any HR monitor and any number of websites to make up a VO2 number just as well as 4th Frontier. My bad for thinking this would be a good tool for that, and I wish I had done more research before I spent this much money and the paid for the premium subscription. I have since canceled that, and now the device is my back-up HR strap - it's actually the back up to my back up, since the X2 is the biggest and clunkiest HR strap/device I've seen since the earliest days of HR monitors in the 80s.

I’m very disappointed with the Fourth Frontier heart monitor. It constantly drops out and goes blank. Yesterday, for example, it dropped out more than 10 times in a one hour ride. I asked for a full refund and the company totally blew me off!!! It cost over $500 !!!!! It’s incredibly annoying and frustrating. My Garmin never drops out. I recommend against buying it.

I bought the X plus with the goal of full-time AF monitoring. I run frequently and wanted to know if arrhythmias were related to exercise as well. I have been disappointed in both, but mostly for running. Almost every run, the X plus wil start out recording, then show “unrecordable” or will be unable to interpret the rhythm, “indeterminate”. I have abandoned the X plus and now wear my Apple Watch 24/7 and it gives me Afib burden. This is more useful than the X plus. X plus is a great idea gone awry: great hopes but poor delivery. Support suggestions were not of much use. My Apple Watch has been much more reliable, even though Apple Watch does not monitor full-time and could miss a brief AF episode.

I purchased the Frontier X 2 on 14 Feb 2024. It stopped working on September 8, 2025. I contacted support. Unit was assessed directly by a rep (via online meeting) and determined to be defective. No refund or exchange was issued because unit had not been purchased though a channel Frontier recognise. Even though the unit was authentic, they did not stand by the product nor recalled to inspect closer to determine what had gone wrong. Cost of unit was 450AUD and didn’t even last 2 years. Not great value. Frontier offered a 30% discount on a new unit that on the website is nearly 600 USD (and offered with a standard 25% off). Why would I buy again, even with a very poor discount, based on durability experienced? If the unit is authentic then stand by it.

I purchased a Frontier X2 from Amazon on the understanding that I could use it to monitor arrhythmias, but belatedly discovered a comparison between the X2 and X Plus, which made it clear that only the X Plus could be used for this function and that it was a prescription-only device. The website really doesn't make this clear and it's ridiculous to offer a continuous ECG monitoring device that doesn't include analysis of arrhythmias. So, the X2 has been returned to Amazon.

Not sure where all these other reviews have come from but in general, for a device that costs in excess of £350 - it's very poor. I use the HRM for variety of exercises - mainly treadmill running, HIT and kickboxing. My main concern and issue is the amount of 'noisy rhythm' that gets reported, generally resulting in a useless and overpriced HRM unfortunately. My past 4 activities have resulted in 27%, 40%, 30%, and even one activity had 80% noisy rhythm. Customer service informs me of the usual tactics to ensure contact, proper position etc. But the amount of items that can seem to interfere with this device is crazy. Zips or metal on your workout gear, even static generated by your clothing can cause interference. For a device that costs this much, that is just plain ridiculous. Back to Garmin and Polar it is.

Bought what I consider to be a very expensive heart rate monitor, only to receive a clearly used item. It had signs of use (grime from prior owner) as well as a charging cable that was not OEM (magnetic connection type thay connects to multiple usb tip types. It acrually had the prior owner's USB tip still in the monitor itself. I did not get the protective plug for the charging port when not charging. After first use, the device basically bricked and will not take a charge. I can't speak to any follow up, but this is either a shady business practice or really terrible quality control, or possibly both. Be wary of purchasing as other users have reported receiving used items as well with no up front disclaimer. **Update** The company did resolve the situation to my satisfaction by offering a full refund of the purchase price. I am still disappointed in the situation, but pleased they were agreeable to a resolution.

A good heart rate monitor and found it accurate in terms of HR compared to several other devices. The ECG I would say was questionable hence the 3 stars constantly get the other rhythm been impossible to find out what this relates to. I am keeping if it due to the breathing rate which I am keen to explore more and it is an accurate HR but as far as ECG I have no confidence in the accuracy. Forgot to add the forum is a complete waste of time posted and nearlt 2 weeks the posts are still in moderation reduced review to 2 stars - could be so much better with a decent forum and support service