Comparison

Polar Flow vs Treadmill Smart Speed

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Polar Flow

This app helps you track daily activity, analyze workouts with detailed metrics, and gain insights into sleep patterns and recovery. It allows for device management, route planning, and seamless syncing with other popular fitness platforms.

Highlights
  • Activity Tracking
  • Training Analysis
  • Sleep Insights
  • Training Load & Recovery
  • Device & Profile Management
  • Wireless Syncing
  • Third-Party Service Integration
Features
Read full description

Polar Flow: Your Personal Sports, Fitness, and Health Companion The exclusive app designed to maximize the potential of your Polar devices. Key Features: Activity Tracking: Monitor your daily activity, steps, calories burned, and distance to stay motivated throughout the day. Training Analysis: Dive deep into your workouts with detailed data on heart rate, speed, pace, distance, power, and more. Understand the impact of each session and optimize your training routines. Sleep Insights: Discover how well you sleep with advanced sleep tracking. Get feedback on sleep stages and quality to improve your rest and recovery. See how sleep boosts your day and track skin temperature changes. Training Load & Recovery: Understand how your training sessions strain your body and get recommendations on recovery time to prevent overtraining. Manage your watch and profile: Customize and manage your Polar device, Sports profiles for different activities, Routes, and Training Targets. Wireless Syncing: Automatically sync data from your Polar devices for real-time updates, notifications, and other insights. Stay Connected: Connect your profile and sync your data with Strava, TrainingPeaks, Adidas, komoot, and many other services. Why Choose Polar Flow? Personalized Guidance: Receive personalized feedback and guidance and understand your progress. Comprehensive Ecosystem: Integrates seamlessly with Polar watches, heart rate monitors, and more for a holistic experience. User-Friendly Interface: Navigate your data effortlessly with our intuitive and clean design. Notification support: Your Polar watch will receive the same notifications as your phone screen—incoming calls, messages, and app notifications. Secure and Private: Your data is safely stored and protected, giving you peace of mind as you focus on your journey. Polar Flow app allows you to share some of your wellness data with Apple Health. This includes details of your training, your heart rate, and steps. Please note Polar Flow app is not intended for medical or diagnostic use. Get Started Today! Download Polar Flow and unlock the full potential of your Polar devices. You can find more info at https://www.polar.com/flow Connect with us! Instagram: www.instagram.com/polarglobal Facebook: www.facebook.com/polarglobal YouTube: www.youtube.com/polarglobal Find out more about Polar products at https://www.polar.com/en/products

About

Treadmill Smart Speed

This app transmits your treadmill running speed from your iPhone or Apple Watch to a receiving device via Bluetooth. It offers multiple input methods, including manual treadmill speed selection, iPhone motion sensing, and Apple Watch data integration for speed, cadence, and heart rate.

Highlights
  • Transmit treadmill speed via Bluetooth
  • iPhone motion sensor speed estimation
  • Apple Watch speed, cadence, and heart rate transmission
  • Manual speed control via crown
  • Integrates with iPhone Health App
  • Compatible with BLE 4.0 Macs
Features
Read full description

Your treadmill, on Zwift. Treadmill Smart Speed turns your iPhone into a Bluetooth running speed and incline sensor. Set the speed you are running on screen and your iPhone broadcasts it, exactly as a footpod would — so Zwift, and any other app that reads a running sensor, sees your treadmill. No footpod, no treadmill upgrade, no extra hardware. GETTING CONNECTED 1. Start pairing in Zwift. Open the pairing screen and choose the run speed sensor slot. 2. Look for this iPhone by its own name. The app cannot change how it appears — to change what Zwift shows, rename the phone in Settings › General › About › Name. 3. Wait for the pill to turn green. It reads Connected once a fitness app is receiving speed. Until then it reads Discoverable. BUILT TO BE READ MID-RUN The screen is made to be read at arm's length, in a dim room, while you are running. The speed being broadcast owns the display, and every control sits in the half a thumb reaches. • A large speed readout with your current pace beneath it • Plus and minus keys that step in 0.1 increments • Six presets you set to your own paces, one tap each • Incline, sent alongside speed • Metric or imperial, chosen separately for speed and for pace • Keeps broadcasting in the background, so glancing at another app does not drop the connection APPLE WATCH The Apple Watch app estimates your speed and cadence from your wrist and reads your heart rate, then streams them to your iPhone. Your iPhone broadcasts the speed, and your heart rate as a heart-rate sensor that Zwift can pair too. Your run is saved to Health as a workout. JUST RUN No app to send the speed to? Choose Just Run at the bottom of the speed source list and your iPhone records the run on its own. Set the speed to match the treadmill's console and run through a 3D park, as a man or a woman. Every kilometre or mile has a gate: run through it for your split, a tap and a burst of confetti. Each run is kept on your iPhone with its time, distance and pace. Match the distance to the treadmill's display afterwards, and export the run as a TCX file to share or save. The last 50 runs are kept, and you can delete any of them. IF YOU BOUGHT THE ORIGINAL APP It stays yours. Everything in this version is free for you, for ever — no subscription, nothing to restore. It is recognised automatically from your Apple Account, on any of your devices. FREE TO TRY Every feature is free for a 10-minute run, with an hour between free runs. When a free run ends, the speed sent drops to zero, and a Just Run run is saved up to that moment, until you unlock. Unlock forever is a one-time purchase with no subscription. Every run is then unlimited, and the unlock is shared with your family through Family Sharing. The price is shown before you buy. Privacy policy: https://appyappster.com/privacy Support: https://appyappster.com/support

Screenshots

Polar Flow4 screens
Treadmill Smart Speed4 screens

Verdict

The call

The clearest difference is rating: Polar Flow at 4.6 against Treadmill Smart Speed's 3.3. Polar Flow also leads on ratings volume (50K vs 24). Treadmill Smart Speed's advantage is monetization model (free vs free with in-app purchases) and update cadence (weekly vs monthly). On price, review sentiment, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Polar Flow sells 1 in-app purchase, starting at $8.99 per month and Treadmill Smart Speed sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Polar Flow holds the better App Store score, 4.6 against 3.3. That said, the two scores are not equally well evidenced: Polar Flow has 50K ratings behind it against 24, so its average is the more settled of the two. Written reviews complicate that: 50% of Polar Flow's written reviews are positive against 53% of Treadmill Smart Speed's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Polar Flow ships an update monthly, Treadmill Smart Speed weekly. The most recent releases landed on October 31, 2026 and October 29, 2026 respectively.

Scorecard4 real differences · 6 level
Polar Flow versus Treadmill Smart Speed: the parameters behind the verdict, then further details
ParameterPolar FlowTreadmill Smart Speed
PriceFreeFree
Rating4.6 (50K ratings) — better3.3 (24 ratings)
Positive reviews49.6% of reviews53.4% of reviews — better
Number of ratings50K — better24
Update frequencyMonthlyWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPadiPhone, Apple Watch
Requires iOS17.017.0
Further details — not scored
Size189 MB65 MB
Age rating4++4
DeveloperPolar ElectroAppyAppster Ltd

Customer experience

Polar Flow

All ratings50,010 ratings
Positive91.3%
Neutral4.5%
Negative4.2%
Written reviews2,215 reviews
Positive49.6%
Neutral11.2%
Negative39.2%

Treadmill Smart Speed

All ratings24 ratings
Positive58.3%
Neutral4.2%
Negative37.5%
Written reviews58 reviews
Positive53.4%
Neutral3.4%
Negative43.1%

User reviews

Polar Flow

From 50K App Store ratings

What we love

  • 🚀 Accurate heart rate monitoring
  • 🔋 Good battery life
  • 👍 Detailed workout data and analysis
  • 👍 Intuitive and user-friendly app
  • 👍 Seamless syncing with Polar devices

Room to improve

  • 🐛 Connectivity and syncing issues
  • 🐛 Unreliable sleep tracking
  • 🐛 Slow GPS initialization
  • 👎 Cluttered and confusing app interface
  • 👎 Limited customization options

Treadmill Smart Speed

From 24 App Store ratings

What we love

  • 👍 Works with Zwift
  • 💰 Affordable alternative
  • 🏃‍♀️ Enables Zwift running
  • ✅ Solves treadmill speed issues
  • 💡 Good for budget-conscious users

Room to improve

  • 🐛 Connection issues
  • 🐛 Speed not detected
  • 🐛 Laggy updates
  • 🐛 Accelerometer mode unreliable
  • 🐛 Disclaimer pops up frequently

Bugs and requests

Polar Flow

Reported bugs

3 issues
  • App crashes during syncing
  • Inconsistent data sync between watch and app
  • Firmware updates causing loss of user data

Requested features

4 requests
  • Ability to manually edit workout data
  • Integration with more third-party apps
  • More advanced training programs and coaching
  • Improved sleep tracking and analysis

Treadmill Smart Speed

Reported bugs

24 issues
  • Problems reported with Zwift connectivity
  • Doesn't show up on Bluetooth in Zwift
  • Slow response time from armband mode
  • Speed not detected in Zwift
  • Intermittent information transmission
Show 19 more
  • Hefty lag in updating speed on Zwift
  • Accelerometer mode largely useless
  • Disclaimer needs to be tapped away every time
  • Armband doesn't work
  • Does not transfer right speed
  • Connected to Zwift but not working
  • Doesn't connect to Zwift
  • Not working out of a sudden
  • Disconnects every time
  • Bluetooth connectivity with Zwift issue
  • iPhone Speed Sensor doesn't work
  • Apple Watch app says 'not Connected to iPhone'
  • No data transmitted to Zwift
  • Doesn't work
  • No support from link
  • Can't get any feedback on iPhone
  • App did not work
  • Will not pair with Zwift
  • New update won't allow update on iPad Pro

Requested features

7 requests
  • Improve response time for armband mode
  • Allow app to work in background
  • Develop for Zwift bike with Power (Watt)
  • Make app available in more countries
  • Provide instructions for Apple TV connection
Show 2 more
  • Forward other BLE sensors (heart rate, cadence) for Apple TV
  • UI polish

In-app purchases

1 purchases

Polar Flow

Subscriptions1
  • Polar Fitness Program1 Month trial$8.991 Month
1 purchases

Treadmill Smart Speed

One-time1
  • Unlock forever$9.99

Questions

Is Polar Flow free?
Polar Flow is free to download, with in-app purchases available.
Is Treadmill Smart Speed free?
Treadmill Smart Speed is free to download, with in-app purchases available.
Which has better reviews, Polar Flow or Treadmill Smart Speed?
Polar Flow is rated higher. Polar Flow averages 4.6 out of 5 from 50K ratings, while Treadmill Smart Speed averages 3.3 from 24 ratings.
Do Polar Flow or Treadmill Smart Speed have ads?
Neither Polar Flow nor Treadmill Smart Speed shows ads.
Which is updated more often, Polar Flow or Treadmill Smart Speed?
Polar Flow ships an update monthly, and Treadmill Smart Speed weekly. Most recently, Polar Flow was updated on October 31, 2026 and Treadmill Smart Speed on October 29, 2026.

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