# CORE Thermal Sensor — user reviews > 30 indexed App Store user reviews of CORE Thermal Sensor by greenteg AG, rated 2.52/5 from 33 ratings. - Source: https://appshunter.io/ios/app/core-thermal-sensor/id1521866309/reviews - App overview in markdown: https://appshunter.io/ios/app/core-thermal-sensor/id1521866309.md - Rating breakdown: 5★ 6 · 4★ 2 · 3★ 6 · 2★ 6 · 1★ 12 ## Newest reviews (10 of 30) ### 2/5 — Work in progress *2025-04-22, version 2.4.0* This app leaves something to be desired. After initial download it signaled that an update was needed. The update would not download despite connection with a rapid local network. Multiple attempta at different times eventually resulted in success. Interaction with customer service was also frustratingly slow. Caveat emptor ### 2/5 — Great product ruined by app *2025-04-02, version 2.3.3* The product itself is revolutionary. But the app ‘experience’ is horrifying. Can’t justify upgrading device until app is fixed. But it seems to get worse, not better. Buggy, laggy, etc ### 2/5 — Average app even more average device. *2025-03-09, version 2.3.3* The app is average and does not let you do anything other than see recorded data. Incredibly frustrating when the core sensor doesn’t connect to your heart rate monitor as the app says “improved accuracy with heart rate” what it should say is there is zero data recorded when there is no heart rate attached. The core sensor itself is useless without a heart rate monitor as it doesn’t detect any strain and therefore doesn’t give you a reference to your heat adaptation. Why they don’t sell this with a heart monitor or make it very clear that it needs to have one with with it to be any use is beyond me -very disappointing for something that’s quite expensive and has a very specific use. ### 2/5 — Useless without Apple health integration *2024-10-16, version 2.3.2* Multiple years later, there’s still no Apple health integration. ### 3/5 — Great start, needs to continue progression. *2024-08-03, version 2.3.1* The app could use some work for ease of use. The data is a little difficult for the non sports pro to understand. Despite not being for medical use, I am using the device to monitor body temperature to see how well my body is regulating temperature since some illnesses cause difficulty with body temp regulation. For that reason, many of the biometrics are of little to no use since I’m not training, but monitoring. My biggest issue is that I cannot sync data with Apple Health—only with my Apple Watch. Additionally, my iWatch has a heart monitor, and I keep it set to continuously monitor, the Core device does not recognize that device data. I am, however, really, really pleased with the temperature monitoring and the device—but would love to see some other functions and compatibility introduced in the app. ### 2/5 — does not work on ipad landscape *2024-07-11, version 2.3.1* Does not work on ipad landscape. Cuts off a portion of the screen leaving a huge black space to the right. ### 2/5 — Ok *2022-10-25* The core temperature graph within the app needs to read 0.1 increments on the y axis as only showing 0.5 increments is useless when this is such a great difference in temperature. Also data in Garmin connect is useless as only reads in whole numbers ie. 37 or 38. And and integration with TrainingPeaks would be helpful. **Developer response:** Thank you very much for this feedback. We believe that the issue with the graph in the app is solved with the latest update. Please contact us on info@corebodytemp.com about the Garmin Connect app issue. The integration with TrainingPeaks is in development, please stay tuned! ### 1/5 — Unable to use history view or pair device *2022-06-20, version 1.3.5* Had issues with some of the sensors and am unable to fetch the data. ### 3/5 — Won’t change from Celsius to Fahrenheit *2022-05-21, version 1.3.5* App works ok, wish that there was more information about how to use the device in the app, and that you could export a record of your temperature. But the fact that there is an option in the settings to change from Celsius to Fahrenheit and that the option does nothing is oddly upsetting. Wish it worked. ### 3/5 — Works ok *2022-02-04, version 1.3.5* Can't change units to Fahrenheit and occasionally switches from the temp monitoring screen back to the main screen and loses the temperature history. ## Most critical reviews (10 lowest-rated) ### 1/5 — Great potential but….complex connectivity zero support. *2026-06-25, version 2.5.3* Love the intentions but the app is cumbersome the connectivity very fragile and in consistent. Analysis shows data that is not on the dash board. Paring with HRMs also inconsistent and unreliable if the monitor is in use by any other app/ device. My big bugbear is the battery retention, use one and leave it with 60% return a week later and the battery is dead and the fact it’s a unique adaptor is also a pain.i like the direction it’s sending me it’s just the journey is not as enjoyable and easy as it should be data captured on a Wahoo missed by this app, as such no value in wearing. Garbage is my last eat opinion . ### 1/5 — Buggy and hard to get hold of support *2025-12-28, version 2.5.1* Won’t connect reliably with tp link Bluetooth adapter and disconnects from Zwift if companion app is in background unlike other Bluetooth sensors. ### 1/5 — Don’t waste your time *2025-10-22, version 2.5.0* Attempted to purchase one of these to track body temp while training. On 2 attempts core failed to ship the device in a timely manner or at all. Waited weeks on both attempts to get the device only to hear excuses like it was shipped back “we’re not sure why”. For the money they’re asking for this, it’s not worth it. ### 1/5 — Cannot get past setup screen *2025-09-27, version 2.4.0* IOS 26 Cannot even get past the initial setup. Just get Failed to Save Preferences no matter what I choose. ### 1/5 — App can not to open up *2025-07-16, version 2.4.0* The app can not to open up normally. ### 1/5 — They’re good at accepting your payment. So far, nothing else. *2025-07-10* I’ve placed my order four days ago. It hadn’t shipped yet. They haven’t replied to any of my messages. So far, this smells like pure techbro hype: they over promise and don’t deliver. But maybe the product will be fantastic. Assuming it gets to me… ### 1/5 — Not ready for prime time *2024-11-30* I’ve had this device for 2+ years. It works okay for getting core body temp read in to Garmin Connect, albeit with little to no guidance on how to really use the data. Unfortunately, for only about 3 out of 5 exercise sessions can I get the CORE app on the iPad or on my Samsung phone to read the data. This is after following all the directions and trying all troubleshooting steps. It seems a little wacky that Garmin can ingest and present CORE data, but CORE can’t, but that’s where it stands. **Developer response:** Thank you for your honest feedback. We would very much like to understand the root cause of the problems you are facing with the CORE app. We kindly invite you to contact us on www.corebodytemp.com to get the problems sorted. ### 1/5 — Half Baked *2024-10-26, version 2.3.2* The update screen is stuck on saying it’s updating. It’s stuck on saying it’s calibrating. It can’t find my Polar H10 heart rate but other apps have no problem finding it. They need to put my resources on the app, or folks are just going to have to wait a year for them to slowly roll out updates. ### 1/5 — Doesn’t work *2024-10-09, version 2.3.2* Won’t get past set up process.?? ### 1/5 — Not comparable. Yet? *2023-12-08, version 2.2.8* Was looking for an app to let me see and record body temperature for my series 9. Downloaded it on my watch. Forced to open on my phone create an account (In which it will not let me delete the account now) launched the app on my watch with the phone app running. NOTHING HAPPENS. Nothing at all. Pairing a device only works if you purchase there white bookmark looking thing. This app is just pointless. How does Apples review process even allow apps like this? Screw sideloading issue coming in the next year or so. They can’t even get apps that work reviewed correctly. Wish I could give 0 stars. ## Most praised reviews (10 highest-rated) ### 5/5 — Quality *2024-12-03, version 2.3.3* Love this, I’m still in the testing phase and it does not take me a lot to get to Z4 with no fan on, bib tights, sleeveless base layer and a thermal top so I’m actually testing trying to get heat out of my body ### 5/5 — Device works well - connects to my Wahoo device. App adequate. *2024-06-29, version 2.3.0* The device itself works well and certainly gives a pretty good/accurate idea of body core body temperature. I bike in western Colorado - hot and dry in summer and great climbs. I can see where my body temperature is climbing - hot - and what it settles down to when not climbing. Useful i am better at hydrating using this device. I can see my body temperature on my Wahoo unit (the Wahoo unit automatically converts to degrees Fahrenheit) while biking (along with speed, heart rate, watts power, cadence, and when I am using a Supersapiens patch, blood glucose). The app is ok. It has a section to customize whether you want to see temperature readings in degrees centigrade or fahrenheit but I have never been able to make it change. That the Wahoo unit does that makes it nice for when I am actually raising body temperature. The device is good the app adequate - if you like to keep track of your numbers this is another somewhat magical device to give you body temperature reading. ### 5/5 — Another Dimension of Data *2022-12-28, version 2.2.3* CORE fits right into the next dimension of training -- what your current workload is doing to your body, and how can you manage it. It winter here now, so racking up the data. My key races are in the heat of the summer, and as a 81kg athlete I pay a heavy price on the run. The CORE will be an integral part of preparing for those conditions and executing in them as well. Don't wait! ### 4/5 — Apple Health and Strava integration Needed *2023-04-01, version 2.2.5* Good app/ sensor but he doesn’t integrate with neither Apple health kit or Strava. Also app graphic is not brilliant either. ### 4/5 — Heat Temp Training *2022-12-06, version 2.2.1* I have only used the CORE Sensor and App version 2.2.2 for a few weeks. It seems greatly improved from the other reviews I see here. It shows Fahrenheit or Celsius. I have mine set to Fahrenheit. I recommend getting familiar with the Sensor with one’s HRM Strap by wearing it around the house or while sleeping to see the baseline resultsover several hours or 12 hours. The rechargeable battery life seems to last, in other words, it drains slowly. The two devices must be turned on the watch settings to get the HRM data to flow (download) to the CORE App. I am using it with a Garmin EPIX Gen2 Watch and the Garmin HRM-Pro Plus Running Strap (with Ant+ and Bluetooth). The CORE Sensor pairs to the HRM which communicates both via Ant+ to the watch. Both the New Garmin HRM-Pro Plus and the CORE sensor can communiate to the CORE App so the App can download the Heart Rate Data from the HRM Pro Plus and the CORE Temp and Skin Temp. These are graphed in the App. I have the CORE data-field on one of my Run, Track Run, Treadmill Data Screens. Because the EPIX has a outside temp sensor, I put that field on a separate screen to understand the difference between my CORE temp and the outside temp the watch detects. From my reading, Heat Temp training is akin to Heart Rate Training. If you train at an elevated CORE Temperature at few times a week, one’s running or biking performance, this greatly improves performance and Temp awareness and its impact on Pace and endurance. I bought it to better understand the CORE temp zones and not to exceed the sweet spot which ultimately degrades performance. I watched a number of CORE YouTube Videos. As an older runner I also wanted to know my CORE Temp when training outside on hot days or during a summer half marathon so as not to injure myself. I am starting to experiment with the levels on a treadmill. I am also starting to use the Airofit Respiratory Trainer to improve my breathing, proper breathing and expanded lung capacity can help with reducing CORE Temp to get to the right CORE Zone Temp. The Sensor seems to do that but I admit I am a novice with this type of training but it is one more tool in the Tool Box. One recommendation I would make is to modify the datafield into a gauge on the watchface similar to the Garmin heart rate zone Gauges in style, this will create a uniformity in flipping screens on the watch since I monitor Heart Rate Data. I would give it five stars if they had a CORE Temp Zone Gauge on the Garmin the same as in the App. Right now the datafield shows the CORE temp, not the CORE Temp in relation to the zones. This is fine but could be improved when fatigued at the end of a race. . ### 3/5 — Potential not realized *2026-06-01, version 2.5.3* I’ve been using the core 2 for over a year. This app is half baked. Connection to the core 2 sensor can be very frustrating. There is significant lag with readings. I often use the app to track my heat strain in real time, but the app doesn’t reliably tabulate either time in zone. I’ve been riding for an hour as I write this and all the zones on the histogram say zero. The daily heat training bar also says zero. So you can’t use a daily heat training load as a daily end point for your training. Also, when logging passive heat training, it would be nice if it calculated how much time you needed to spend doing each activity to achieve a particular daily heat training load. E.g. based on the ride I’m doing now, it would be nice if the app told me I had to do 20 minutes of sauna to achieve the daily heat load of 10. ### 3/5 — Could be great! *2025-06-03, version 2.4.0* Useful training tool let down by a slow app. The live metrics seem to work but the time in zone, heat training load and heat adaption score can be very slow to update for some reason. Surely this is an easy fix! ### 3/5 — New sensort *2025-05-29, version 2.4.0* I just changed to the new sensor. Everything was fine with the old one but now the data from todays ride/effort is not transfered to my « overall heat score ». It just stays at 0. It feels like lates UI update about a month or two ago doesn’t work well ### 3/5 — Added passive, doesnt work *2025-04-24, version 2.4.0* The adding of passive heat is great but setting the date doesn’t work… ### 3/5 — Behaving better lately *2024-12-09, version 2.3.3* This is an update (and upgrade) of an earlier review. I’ve had this device for 2+ years. It works okay for getting core body temp read in to Garmin Connect, albeit with relatively little guidance on how to really use the data. Routinely, I experience difficulty getting the app to read history data from the sensor. It connects, claims to be getting current data—occasionally toggling to the ‘getting historical data’ message—but won’t show the data. Garmin Connect sees the data immediately after completion of the run or ride, but the CORE app doesn’t. Then usually the data will show up in the app a few days later. It feels like the connection should be faster and more robust; also there should be better diagnostic message of what’s going on. I appreciate that the device needs to be parsimonious with battery life, but the Android/iOS apps don’t need to be. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-29.*