CMF Watch 3 Pro: A device I want to recommend but cannot ... at least not yet

CMF1_hacker · 2025-09-29T13:35:46+00:00

# tl;dr #3 this watch is now on sale for £69 an Amazon. It's an excellent fitness tracker for beginning people and decent if you don't want to spend up to £249 on a GPS watch for serious event. It's great for indoor training when your phone is around. # **tl;dr #2** Based of this thread, especially @"JonBek"#109689 , and various discussions with support from both of us, see post number 13 below, more capability is possible out of the hardware in its default state, thus my **score has been revised to a 7/10. It remains somewhat clunky, but for the hardware it is priced very competitively (£79-89 street price).** I am ditching my Garmin and HR strap and this does everything I need for someone logging 2 cycles one gym session per day. # **tl;dr** I’m not going to go into all of the detailed specs as every other reviewer will. I’m also not going to provide tons of colour photos/videos as everyone else will. In short, I’m looking for an inexpensive GPS-enabled sport watch (RRP: £99 but street price is around £85) that will replace my Garmin Forerunner 45 and in that role I give the current CMFW3P a 4 out of 10. However, I am trying to work judiciously with cmf/NOTHING to make one simple change/bug fix that would bring it an 9 out of 10 and make a stellar value fitness watch. You'll have to read until the end to see what that proposed change is. # Disclaimer This watch was provided as part of the Nothing Community Review Programme. I have used this watch for 28 days and will return it. I sincerely hope that NOTHING makes the final improvement required to make this watch a stellar value as I would spend my own money on it when that change is made (even at the full RRP of £99). # Initial impressions Standard nice NOTHING-designed packaging. I went with orange model and man that strap is bright and it looks very cheap/fun. Based on the colour and the visual texture, I expected it to feel like a cheapo watch out of a 50p claw machine but it’s actually quite comfortable. Also, the metal watch case looks and feels quite nice. I did get some cement and some paint on the watch case and the band and was able to clean it after somewhat easily after some DIY. The Garmin band does irritate my skin, I believe it has some silicone, and I find the CMF3WP much more comfortable. Thus, I conclude that watch does live up to its cmf (colours, materials, finish) moniker remarkably well. I only used the single watchface (in the photos) during the testing and found it great. The watch itself fits my slender wrist quite well and I wouldn’t want a larger diameter waterface bigger and I’m 188cm and somewhat muscular (95kg). Also, it fits under slim-fit dress shirt cuffs well also and doesn’t seem out of place with my other apparel (coloured trousers/blazers). It looks quirky and I would guess most colleagues would speculate a £250-300 RRP if they were asked. The screen size was good and the text was very clear and the interface was snappy while retaining NOTHING design cues (NDot fonts and the like from other cmf products). The only slightly negative component so far was that the AMOLED screen was challenging to see with my polarised sunglasses on, which is a slight issue when on my bicycle. I have not compared this to other AMOLED watches, nor have I measured nits, and I would speculate this is the case with most of them, unless they’re very, very bright. (I can see the NP3 screen with these sunglasses on, but the CMF1 screen much less so). [upl-image-preview uuid=097a56f2-c59d-491b-97b2-76907a9b9d33 url=https://cdn.nothing.community/2025-09-29/1759151922-437434-whatsapp-image-2025-09-29-at-141809.jpg alt={TEXT?}] # My specific use case For a middle-aged (nearing 50) adult, I believe I am reasonably active. MON to FRI, my daily schedule includes 3-4 miles of daily cycling to my children’s school to drop them off and over to the my office, I also usually do between 30 and 60 minutes of daily cardio at the gym (usually indoor rowing) and also walk and additional 5k and 10k steps daily. I usually log the data, like most of middle-aged people with too much time, and I’ve used STRAVA since 2010 or so. Thus, my use case requires fast and accurate GPS, with good HR monitoring that pulls through to STRAVA. I’d also like a good battery, so it won’t have to sit on the charger. Usually, I’d record about 45-90 mins of exercise per day with GPS/HR. I found that the CMFW3P uses about 10% of battery for 1h of fitness recording. Thus, I filled up the phone every 5-6 days or so. On the weekends, I usually walk about 7-8 miles/day and sometimes, we use the bikes as a family. So, I’d try to charge every 3-4 days or when I remembered. I’m annoyed that all of the watches have different chargers, and I only had one charger, which stayed at the office during this test. If I owned it full-time, I’d buy a second charger for home like with my Garmin. # Quality of GPS tracking I’m a dork, so I wore my Garmin FR45 and the CMFW3P at the same time for several outdoor exercises and you can see the comparison in the table below. [upl-image-preview uuid=0e7b98a8-3da9-4e64-9fdf-4ca838659e71 url=https://cdn.nothing.community/2025-09-29/1759149167-78377-whatsapp-image-2025-09-29-at-133214.jpg alt={TEXT?}] The GPS distance was usually within 2-3% of each other, which I would consider within the error or two devices. [upl-image-preview uuid=570f15c3-9fd8-45e3-b0cc-05e765db9341 url=https://cdn.nothing.community/2025-09-29/1759149193-428591-screenshot-2025-09-29-at-094845.png alt={TEXT?}] The tracking looks on the CMFW3P looks more coarsely recorded (fewer time points over same time) than on the Garmin (more timepoints over same time), so if absolute precision is paramount, this might not be the device for you CMFW3P [upl-image-preview uuid=54073f4b-5a9d-4bab-ac11-e1339add160f url=https://cdn.nothing.community/2025-09-29/1759149243-878152-screenshot-2025-09-29-at-100109.png alt={TEXT?}] FR45 [upl-image-preview uuid=276290ff-fc68-4f62-93f5-cbd2ea1e7c03 url=https://cdn.nothing.community/2025-09-29/1759149243-983173-screenshot-2025-09-29-at-100209.png alt={TEXT?}] However, I’m not an Olympic athlete and 2-3% is fine with me. If I jog a 25m00s 5K or a 24m55s 5K, I couldn’t care less. I assume that there are trade-offs being made for granularity of tracking data against battery life. Also, the CMFW3P captured the GPS signal very quickly, which was nice as my old Garmin was somewhat slow. Thus, I’m pleasantly surprised with the GPS quality. # Quality of HR monitoring The second major component that I deemed necessary was the HR tracking. Over the cycling and walking events, I compared the Garmin FR45 against the CMFW3P and found them exceedingly similar, so this was excellent. The set-up in the gym itself is much more complex as I have a heartrate strap (Decathlon) that connects to my Garmin FR45 and to the SkillRow rowing machine. The Garmin FR45 then uploads the HR data to Strava. Thus, I was comparing the CMFW3P to my Decathlon HR strap and I had no expectation of similar data. I was extremely surprised how close they were both on steady-state workouts and workouts where the HR changes rapidly like intervals. STRAVA (Garmin FR45): [upl-image-preview uuid=36012698-0959-4ece-94a5-66c4a4c48c79 url=https://cdn.nothing.community/2025-09-29/1759150776-887237-whatsapp-image-2025-09-29-at-135816-1.jpg alt={TEXT?}] CMF WATCH 3 PRO [upl-image-preview uuid=7165da6d-7906-4a55-b685-fd5089de5f98 url=https://cdn.nothing.community/2025-09-29/1759150804-530869-whatsapp-image-2025-09-29-at-135816.jpg alt={TEXT?}] # The other fitness bits and the interface with Nothing X Everything one would expect is there. A coach, kcal tracking, steps, etc… I don’t really use this stuff on my Garmin and I didn’t really test it here. It looks correct and relatively consistent with what I saw previously on the Garmin. See screenshots below. [upl-image-preview uuid=67ccd054-723e-4e5e-868c-5b752801e13a url=https://cdn.nothing.community/2025-09-29/1759150908-997097-whatsapp-image-2025-09-29-at-140104.jpg alt={TEXT?}] # The non-fitness bits of the watch (notifications and non-sports stuff) The watchface is bright, the screen sensitivity is good, the layout is good. I turned off my notifications on my Garmin and I forgot how many emails and WhatsApp messages I got per day, i.e. roughly 200. Sometimes they came in bunches, sometime solo. A quick rotation of the wrist and I could view them. The watch looks decent so in meetings it didn’t raise attention to look at it and I could reply on my phone or my laptop if I was waiting for something precise to arrive. I mean, it looks well and works well, the screen is detailed and with the watch face I use, I could see all my notifications and my fitness tracking data easily. It's autumn now in England, so I didn't swim in the ocean with it like I would by FR45. It's only IP68 compared to the FR45 with is good to 50 meters, so there is a real difference there for open sea swimming or pool swimming. # What does NOTHING need to improve for me to recommend this watch This is the crux for me. If they could fix this below, the score would jump from a 4/10 to a 9/10 in value (1 point lost for no swimming certification). Initially, cmf support believed that HR pulled through to STRAVA, which it doesn't. There's some threads on nothing.community about this as well. (a) The HR/cadence data does not pull through to STRAVA. I have included a walk from the office to school wearing both watches. The Garmin pushes the .GPX (GPS data), HR and cadence over to Strava for viewing and downloading. The CMFW3P does NOT push the HR data over to STRAVA, only the GPS data, which can be downloaded as a .GPX file (more later). Double watching-wearing episode [upl-image-preview uuid=2b884546-009a-4015-bd52-dc45a7e12e52 url=https://cdn.nothing.community/2025-09-29/1759151156-273903-screenshot-2025-09-29-at-140519.png alt={TEXT?}] CMFW3P data: [upl-image-preview uuid=617e0164-c934-4ece-a173-a5298ad64ad8 url=https://cdn.nothing.community/2025-09-29/1759151178-513426-screenshot-2025-09-29-at-124546.png alt={TEXT?}] FR45 data: [upl-image-preview uuid=5592cd56-74d1-4c2a-b16f-f0a0f02fe540 url=https://cdn.nothing.community/2025-09-29/1759151178-738073-screenshot-2025-09-29-at-124609.png alt={TEXT?}] (b) If only HR data is collected on the CMFW3P, such as with indoor rowing, no event is created in STRAVA, even though the data can be viewed in NOTHING X. I personally feel this is an absolutely essential feature and it’s a dealbreaker for me, and likely for many others, and to be able recommend as this device, this needs to be fixed. There are a few threads on nothing.community stating similar evidence and desires. #### A minor suggestion for improvement I have run the .GPX files from both devices through chatGPT5plus to compare them. As shown above the CMPW3P is more coarse. What I discovered is the CMFW3P records a GPS measurement every 5 seconds only, whereas the Garmin uses adaptive monitoring based on movement speed. It stops amassing GPS data when stationary and reduces the time between collection points when moving rapidly. I don’t think NOTHING needs to execute this, I would recommend an option to set the GPS recording frequency … **perhaps 1s, 3s and 5s per data point, in a similar manner to the HR frequency (which is in minutes),** that I have set to capture every minute. [upl-image-preview uuid=77e62a0b-dfac-4f30-9ac0-74b5d53b6db1 url=https://cdn.nothing.community/2025-09-29/1759151516-559029-screenshot-2025-09-29-at-141120.png alt={TEXT?}] [upl-image-preview uuid=dc7fee58-1751-4620-a994-b91c20e627ea url=https://cdn.nothing.community/2025-09-29/1759151516-700068-screenshot-2025-09-29-at-141139.png alt={TEXT?}] # Next steps with cmf/NOTHING I have fed back these observations to cmdf support via the community testing route and via the standard feedback route with device logs and PDFs of the precise problems and have been contacted by them and we went back-and-forth when I provided more information. I ran the system logs through chatGPT5plus myself and looked through them to see whether I could uncover the problem, but I have run out of time as the academic year is starting here. Until I sat down to write this review, I didn’t appreciate the difference in granularity of the GPS coordinate collections (5 sec between always with the CMFW3P and variable with the FR45), I will make a suggestion to nothing, to provide an option for users to be able to select the frequency. The difference between the distance travelled between the two watches is quite small (1-2%) but if I was doing track workouts on a 400m track, I’d want more then 5 seconds (that would only be 11 data points when I ran my fastest 400m in my life at 51 seconds 😊 and it would result in a funny looking GPS track for a 400m track). # Final verdict It's a really nice piece of kit. It looks good and more importantly it feels good and works well. For the non-fitness person it would be great. Also, if you wanted to get fit there are a ton of motivating/gamifying options that can keep you motivated. If you're more serious, a decent GPS/HR watch with similar options starts at around £249. cmf/NOTHING have a potential blockbuster on their hands at an RRP of £99 that simply needs a few bugs worked out for the fitness freaks to take notice. I hope they respond to this report and if they do, I will update it.

JonBek

Strava got back to me within 24 hours. I have been waiting 3 weeks for any help from Nothing/CMF. CMF/Nothing don’t use the proper API and GPX files strip the HR data. It’s definitely fixable by CMF.
From Strava customer support:

Jimi (Help Center)

Oct 2, 2025, 4:03 AM MDT

Thanks for writing in. It looks like the files coming to us are in .gpx format which removes much of the data, including heart rate, that we are able to display on your activity in Strava.

We suggest reaching out to CMF directly for any questions. To provide some context, we have a publicly available API that hundreds of external developers use to integrate with Strava data. These integrations are built and maintained by those 3rd party developers which means that any troubleshooting questions are better directed their way.

Cheers,
Jimi
Strava Support Team

CMF1_hacker

JonBek reply, that’s what came out of chatGPT5 as well. when both APKs were shared and compared.

I am looking at a workaround at the moment as Health Connect gets all the data from what I understand.

That API is to PULL data from STRAVA unless I’m mistaken?

JonBek

CMF1_hacker Nothing needs to fix the Nothing X app integration to Strava. It’s about time, since this has been an on again off again problem over the last year. Eminently doable. Would be nice if the new Playground and essential apps could make an app to do this. I tried. I am on the waitlist.

CMF1_hacker

JonBek I have found a solution that will bridge Google Fit to Strava. See below,

I need to fine tune it after the children go to bed but I can pull through HR data from indoor activities to STRAVA now

damn, the first is data from an HR strap and a Garmin watch via Garmin Connect. The second is the CMFW3P, where it takes data at lower frequency … I need to ask chatGPT5 what the difference is in resolution, but that overall pattern is stellar

that’s the app below that goes from Google Fit to Strava

here is what chatGPT says about the resolution difference:

ok, after the looking at the HR uploads:

it looks like 3:1 difference in resolution

FR45 (HR strap to watch to STRAVA) 700+ HR measurements for 30mins

CMFW3P to NOTHING X to Google Fit to STRAVA (230 HR data points for 30 mins)

Potential workflow for the CMFW3P to Strava with GPS and HR for indoor and outdoor data:

Reocrd everything in NOTHING X (this will use the Google Health Connect libraries for everything) and turn OFF STRAVA integration and Health Connect on
In app permissions for Health Connect, turn all on. Check the Google Fit can write the route. Also, give Google fit access to Location in app permissions.
Have Health Sync go from Google Fit to Strava as shown below. Google Fit will capture all walking and other small BS, so I filter activities as the following screenshot.

I hope that works and I’ll check it tomorrow with two short rides and the indoor rowing. Currently the HR pulls through to Fit for all three but no GPS to Fit yet (that might be an issue with Location permission or write route data which I think I have fixed).

JonBek

CMF1_hacker Very smart of you. Waiting for you check and to see if the GPS data and route and mileage gets synced to Strava with the heart rate data. Again Nothing should be able to get this to work in the Nothing X app. Hopefully I will hear back from them in a day or two.
In the meantime, I have linked FitBit to Stava in FitnessSyncer and I will see if that works. It’s free for up to 5 fitness apps. I link Stava and RidewithGPS and Garmin Connect and XERT and now FitBit.
https://www.fitnesssyncer.com/

CMF1_hacker

JonBek ok, first test had an auto sync option fail due to battery optimisation. I also have HR pulling through but no GPS.

So, I still need some optimisation. Will look at today when I need a break.

Edit: error might have been forgetting to turn these settings on in Google Fit. Nothing X did record the data, will test later when I go to gym with the walk over and the HR-only rowing.

Edit 2: almost there with a workaround.

Nectar

Hope the watch 4 brings wear os… if not ill renew my galaxy watch 4 to de 8 or 9 the next year…

CMF1_hacker

OK, now I can get NOTHING X to export to Google FIT (GPS and HR) and just for the Strava integration now.

Synopsis as of FRI 3 OCT

I can now get an indoor activity from NOTHING X into Google Fit and into STRAVA as a .fit file. This was not possible with NOTHING X alone as it uses .gpx files (with no HR data).

I have tested every possibility and cannot find a way to make this work with STRAVA as it should.

I guess that’s why it’s ⅓ the price.

I am going to change tack and look at the code with my spare time and determine whether it can be modified simply to work and recommend that to the dev team.

I will keep the HR indoor system through fit working as there’s no other way for it to work.

KEY ISSUES

it seems that NOTHING X only write out to .GPX which will never pull GPS and HR out to STRAVA. Communication with support has not lead to a resolution, so I will try a workout suggested by chatGPT5 when I have a moment:

JonBek

CMF1_hacker CMF just sent me this reply about Heart Rate data. Says HR only gets sent if you start an activity from the phone and not from the watch, if I understand correctly. I will have to try this.

| |
| — |
| |

Thank you for contacting CMF Customer Support.

We do apologize for the late response. We are sorry for the inconvenience that you need to go through. Can you please follow these troubleshooting steps below.

When wearing the watch, heart rate data will only be recorded if you start an outdoor sport with GPS enabled via the Nothing X App.The Nothing X App will sync heart rate data to third-party platforms. However, for specific details on whether the data will be displayed on the third-party platforms, please consult the respective third-party platforms.
We greatly appreciate your patience and understanding. Should you have any further questions or feedback, please do not hesitate to reach out. We are always available to assist you.

Warm Regards,

Mary Cia
CMF Customer Support |

EDIT: Wow! I just tried starting an activity through the Nothing X app. If you start an activity from the phone via Nothing X app, the HR data indeed gets sent to Strava. No clue why HR data doesn’t get sent to Strava when you start an activity from the watch. Still, this should be fixable at some point.

CMF1_hacker

JonBek WHAT?

If I start an activity on the app, it will pull through the HR and GPS to Strava????????

We that’s annoying but not insurmountable.

I’ll try that this morning with a bike.

So I always have to have my phone with me? Or just at the start and maybe that the finish?

UPDATE 7 OCT 2025

As @JonBek noted above, when an activity is started in the NOTHING X app, (1) will pull through GPS and HR data to the STRAVA app as shown below. This is great, albeit somewhat clunky. I haven’t tested it yet, but you need the phone to start the activity and to conclude the activity, as far as I can tell you can’t start/stop it with the watch only and get HR data pulled to STRAVA.

Also, this doesn’t sort out the issue of (2) not allowing non-GPS-enabled activities to be shifted to the STRAVA (like indoor cycling/rowing). I believe I have sorted this out by allowing Health Connect access and then using a third-party app (Health Sync) to pull the data from Health Connect over Health Sync to Strava.

Summary:

It also needs to be tested whether I need my phone all the time for this to work starting from the app. I would hope not but I haven’t tested that.

It is still very clunky but I revise my original estimate to a 7/10 from a 4/10. I am developing a companion app to try and make this smother and will keep this thread updated.

I did get it to upload the rowing but other activities needed to be checked for the sync to work.

The watch seemed to have a slight hiccup for a few seconds there as well.

mjacket

JonBek

Thank you for good information.

I thought that is a limitation for free Strava users.

Following that you shared, I can see now the HR data along with the GPS route on Strava.

But It’s really inconvenient and don’t understand why they made it like this.

I hope Nothing will improve this.

CMF1_hacker

mjacket I tested it again this morning. I have to start the GPS/HR workout on NOTHING X but I can stop it with the watch alone and it pulls through the Strava app correctly.

I’m trying to build a companion app that will accomplish this with the phone only but am time-deprived at the moment.

JonBek

CMF1_hacker Today I tried starting the workout on the phone with Nothing X while outside with GPS signal, and then I left the phone in my mailbox and went for a walk. The workout is cancelled if you leave the phone disconnected from the watch for more than 5 minutes. But you can definitely start the activity on the phone and stop it with the watch and the HR data gets sent to Strava. I use my old iPhone 11 for when I cycle because it’s so much smaller and lighter. I will see if I can have the Nothing X app on 2 phones at once and use the iPhone for cycling activities. I did try using Nothing Ear with Spotify and stopping for Harvest moon pics while walking, and everything works fine while recording an activity, listening to music and using the camera.

From the How-to Page:
How to synchronise app and watch workouts?

After connecting the watch with the Nothing X app and wearing the watch, go to the workout page in the app and start any workout. The watch will display the corresponding workout mode and begin the workout directly.

During synchronised workouts, if the app and watch disconnect, both the app and watch will separately record the workout for up to 5 minutes. If the connection is not restored within 5 minutes, the workout will automatically end on both the app and the watch. If the connection is restored within 5 minutes, the data will synchronise with the watch’s workout data, but the disconnection may result in the app missing some heart rate data."

Coldpaw

For me, the lack of long term support for the previous watches instantly killed the CMF Watch Pro 3. It will be launched and abandoned just like the predecessors.

CMF1_hacker

Coldpaw I don’t really mind to be honest. I look at it as a simple technical device, like my 5-year old Garmin. If it works, why would I need to update it. I’m hoping that coding apps with chatGPT5 is easy and will continue to get easier.

I opened Android studio for the first time and was able to build a companion app called NX Fit Bridge to attempt to merge the GPS data from the watch itself (no phone required to the HR data stored in Health Connect). I think it will take me around 20 hours to cobble something together.

Thus, I don’t really worry about long-term support as I can’t imagine the watches getting any worse than they come out of the box and I can code something in the future. How much support can one expect for £85 or so really?

edit: I have arrived at the best I can do without coding my app, which I’m half way through. I cycle twice every day and work out at leats once. To get all HR/GPS data onto Strava: I have to start the cycling on the phone with the NOTHING X app and can stop it on the watch. The the pushing of the data to health connect via NOTHING X, I can use Health Sync to push the indoor HR data to Strava, without touching the phone.

conclusion: I will continue working on the my “NX Fit Bridge” app.

CMF1_hacker

JonBek I wonder if this is a memory limitation on the phone? I guess this watch won’t technically do what my Garmin does (allow me to go from a GPS-draining long ride/run … hours … without my phone).

That is one way to keep the cost down, so I can’t complain really.

I can’t stomach £300+ for a new watch though.

Thanks for all of your help here.