Polar M400 GPS Watch – User Review | GadFit (Updated 24th October 2015)

August 15, 2015

The Polar M400 has been on the market for about a year now. I recently got my hands on a unit and I know the review is late but a fantastic piece of device deserves a voice. While there are a multitude of GPS enabled watches on the market, the Polar M400 (RRP $179.95) is among a special group that features smart phone notifications; a group that is growing steadily. I’ve been diligently wearing it for about a month now and here’s what I have to say.polar m400 -feature



  • Tracks 24/7 activity. Steps, distance, calories, sleep.
  • Pairs with compatible heart rate monitor to record HR
  • Assisted GPS enabled
  • Audio beeps for alarms, idle alerts and smart notifications for both iOS and Android
  • Sports profiles
  • Waterproof to 30m
  • Fitness tests and running index with Polar’s H7 Bluetooth Smart HRM
  • Back to start feature
  • Up to 8 hours of usage with GPS and HRM connected
  • Up to 24 days in watch mode with daily activity tracking
  • Training and activity benefits


  • Strap is too long and feels plasticky
  • Not vibration enabled


polar m400 -on-handThe Polar M400 wears like a normal watch would. Not too bulky nor too sports like. I have a small wrist and I thought it fit nicely which is rare. The large screen is great for viewing purposes during work outs.polar m400 -facesThe watch face is customisable and you can choose from 4 watch faces. I personally like the one with the activity bar. This is a GPS enabled activity tracker after all.polar m400 -profile-viewThere are a multitude of fitting holes so you can go loose during everyday wear or tighten up ever slightly during your workouts.

Unlike the Polar A300,  the M400 is permanently embedded into the strap so you’re stuck with the colour of watch you purchased. There are a total of 5 buttons on the Polar M400.polar m400 -left-and-right-buttons

  • Back Light
  • Scrolls Up
  • Scrolls Down
  • Back
  • Start/ Commence tracking

I think it’s great Polar stayed away from touchscreen capabilities for sports watches. Perspiration and touch screens just doesn’t go very well.

There are no vibration motors within the Polar M400 so audio beeps are the only form of notification you’ll get. Great on battery saving. Not so great on being discreet during work meetings.polar m400 -with-lightThe display is visible in the day and back light enables visibility in darkness. Unfortunately the back light must be activated manually and there isn’t any function to automatically activate the back light when the wrist is up. That feature would have been great.polar m400 -menuBattery lasts about a week with an hour of training per day and up to 30 days with normal watch functions and activity tracking only.


GPS tracking

polar m400 -with-HRM-and-GPS-okThe Polar M400 is first and foremost a GPS watch. Upon activating the “Start” button, GPS will start searching for signals. Polar has stated that with A-GPS (Assisted GPS), the M400 can search and lock on to GPS faster. You can start recording once the GPS signal hits 100% or “OK”.polar m400 -running-metricsWhile wearing the Polar H7 Bluetooth Smart heart rate monitor and with GPS enabled, you’ll be able to see information like average heart rate (HR) for each lap, pace and duration per lap. There are so many display views I had a hard time deciding which metrics I was really interested in. I

Laps can be set to automatic or manual. The Polar M400 will count laps as every kilometre if set to the metric system under “Settings.” To manually clock a lap, just press the “Start” button.Polar-Flow-app-exercise-trackingThe running route I took was also nicely captured on the map in app. By sliding the progress bar, I was able to examine my progress throughout the run and coincide that with the HR, the pace, total distance covered and lapsed time.polar m400 -after-run-metricsAt the end of the session, the Polar M400 will display a whole series of information which the user can view on the watch or in app. That is if you’re not too tired from the run. I personally like to leave the analysis after a good warm down walk while contemplating the complexities of life 🙂Polar-Flow-exercise-screenA running index score is also be provided. Polar’s running index is the company’s in house researched method of estimating maximal aerobic running performance. This can provide an additional measure of improvements in fitness over time. The Polar Flow app will also provide a snippet of training benefits based on the current sessions.

All Day Activity tracking

Polar-Flow-app-dashboardThe Polar M400 also tracks your activities throughout the day in terms of steps. You’re asked for your profile of physical activity level and the device, the M400 in this case, will work with the app to chart your progress and present it nicely in the mobile app.polar m400 -actvity-barWhat’s really neat is that the Polar M400 will advise you on the duration and type of activities you’re need to hit your goals.

Sleep is also tracked and automated. However, the device only tracks sleep at night. So if you’re napping in the day after a hard workout it’s not going to track that. Neither is there any option to manually track sleep.

Sports profile

This is the other feature of Polar M400 which I particularly liked. As a PE teacher, I engage in at least 2-4 sports and games daily and I normally don’t record all the sessions into the trackers I’m using simply because it’s too tedious. With the M400, I can choose the sport profiles I usually engage in and start tracking when I’m doing those activities. The good thing is all these activities will then be recorded on the Polar Flow web interface or within the Polar Flow app; thus serving as a record of sorts for me.polar m400 -sport-profilesThe sport profiles also allow me to fine tune how each activity is to be tracked. I could tweak the level of audio beeps, whether the activity tracks with heart rate monitors or even GPS. It still requires some planning on my part but Polar has taken care of the main bulk of the tracking.

For example, in outdoor running mode I have the GPS tracking enabled whereas in indoor floorball profileI have the GPS function disabled.

Smart notifications and Inactivity alert

The audio beep within the Polar M400 is used in 3 ways.

  • Alarm
  • Smart notifications
  • Inactivity alerts

You can set the alarm to wake up to and put it on to repeat at the same time every day or simply go off once.polar m400 -smart-notificationsThe smart notifications function is enabled on both compatible iOS and Android devices. You can choose to display bits of the message or not at all. The loudness of the audio beep can also be adjusted though I must advise it’s best to turn it off during a meeting. Unfortunately you can’t choose which mobile app notifications will activate the smart notifications. Neither can you reply with pre-set messages on the Polar M400.

Phone calls will also appear on the Polar M400 as part of smart notifications. You can choose to take the call straight from the watch though you can’t talk to the watch to answer. What it does is allow the phone call to be picked up assuming you have a bluetooth ear piece or you can just whip out the phone and use it normally.

There’s also a neat feature to turn off all the smart notifications at a specified time on a daily basis.Inactivity-Alert-on-Polar-M400Once the Polar M400 detects inactivity after 55 minutes, the inactivity alert will go off prompting you to get up and move. I found this feature particularly useful.


Polar-M400-training-diary-on-app-and-watchYou can also access most of the tracked stats straight from the Polar M400’s diary. Scroll to any of the dates and it can be vastly expanded depending on what took place during those days. I found the information access user friendly and the capability to see past tracked sessions extremely convenient. Very impressive what Polar has done here.

The same information can be found within the Polar Flow app, albeit in a more coloured manner.

Polar Flow Web Platform

Polar-Flow-web-dashboardPolar Flow also has a web interface which you can log into to access your data on a larger display. It is also here you can customise the sports profile and view other user’s progress. Yep, you heard me right, check out other people who are also on Polar Flow and try not to feel bad about your own physical progress.Polar-Flow-web-dashboard-settingsI’ve been on the Polar Flow system for quite a while now and though the device I use changes, the account stays the same. Over time, Polar Flow was able to summarise all my workouts nicely and show the trends. If you refer to the screen grab above, you’ll notice that I spend half my time training without benefits and about 71% of the time is spent running.

Fitness testing with Polar H7

polar m400 Fitness-TestThe Polar M400 pairs readily with the Polar H7 Bluetooth Smart heart rate monitor. With the H7, you can activate the fitness test function which gives you an estimate of your fitness levels over time. You can read more about Polar’s Ownindex here.

This function is also available on the Polar Beat standalone app. Again to be used over time and on a regular basis. Don’t expect to see quantum leaps after every session though. Physiological adaptations take time.


Pairing with other Bluetooth devices: You can also pair the Polar M400 with the Polar Stride Sensor Bluetooth Smart which allows you to get the precise data with regard to running cadence.polar m400 -Trophy-examplesTrophies: The Polar M400 watch and Polar Flow app work in tandem to track your workouts and awards you trophies when you hit new milestones.

Training View: The training view can also be set to light or dark. It’s either light background with dark numbers and letters or dark
background with light numbers and letters.

Back to Start: For those of you who are into running in the wild, you’d be happy to know that the Polar M400 has a “Back to Start” feature that upon activation will display arrows on the watch to guide you back to the start point.polar m400 -with-scoschePairing with other Bluetooth heart rate monitors: Though Polar explicitly stated in the manual that not all Bluetooth heart rate monitors are compatible, I was able to test and sync my trusty Scosche Rhythm+ optical sensor heart rate monitor easily.


If there was a function to enable the back light for long durations, it would be great. Presently I have to continuously activate the back light when lighting is poor and it can get bothersome after a while.

While manual syncing conserves battery, i would have appreciated perhaps automatic syncing once a day at stipulated time. I can sometimes go days without syncing and as a result, not look at the app at all.

Instead of purchasing a stride sensor, it’d be great if Polar could allow users to calibrate distance ran with the accelerometer within the Polar M400 to estimate distance.

Also, I would have liked the ability to reply messages with pre-set replies.

If these few functions can be enabled, I’m sure M400 users will further resist the lure of the next big tracker from other companies.


The Polar M400 scores in many aspects for me. While the GPS and heart rate tracking is a given, I loved the sport profiles, and the smartphone notifications which is currently available on the iOS platform for now only.

In the activity tracking aspect, Polar performed splendidly with its unique way of data presentation in the form of a pie chart which is contrary to graphs used by many other companies.polar m400 -with-backlightsThe M400 also brought with it features like runing index and fitness testing which are actually functions available only on the paid version of the Polar Beat mobile app.

Even though it’s been nearly a year since its release, the Polar M400 is still an excellent piece of fitness device to consider. It punches above its weight compared to other trackers on the market and offers incredible value for money in terms of functions. Throw in a Polar H7 Bluetooth Smart heart rate monitor and you’re en route to some serious training.

The Polar M400 is available in black, white, blue and pink.

Buy the Polar M400 from where there’s usually a slight discount and free delivery depending on where you reside. In return, your purchase helps to fund the running of this site. Thanks for reading!


  • Reply Leo Clarke October 16, 2017 at 11:39 pm

    Hi there, I’m currently looking at this version of the M400 second hand. There seems to be a newer version, do you have any comments about comparison? Cheaper 2nd hand old vs more expensive new…? Thank you for any insight!

    • Reply Michael S October 17, 2017 at 11:44 pm

      Hi Leo,

      You’re absolutely right, there’s the M430 that’s packed with wrist HR measurement and updated sleep tracking metrics from Polar which you might like to take a look really.

      Check it out.

      It really depends on how cheap really. There are options aplenty for GPS watches in the $100 zone so it’ll depend on which platform you’ve been used to.

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