Comparison

Frontier X vs PRO SKI Sensor

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

Head to head
About

Frontier X

Track your heart health and exercise performance with a smart chest strap monitor. Gain detailed insights into heart rate, rhythms, and training load. Receive personalized feedback and alerts to optimize your workouts and understand your body better.

Highlights
  • Heart Health Monitoring
  • Real-time Heart Rate & HRV
  • Breathing Rate & Strain Tracking
  • Activity Recording (24hrs)
  • Personalized Vibration Alerts
  • AI-enabled Training Insights
  • Metabolic Profile Analytics (Premium)
Features
Read full description

With your Frontier X/X2/X3, track your activity including exercise, rest or sleep to get detailed insights on heart health and exercise performance. This companion app allows you to connect with Frontier X2/X3 - a revolutionary chest strap wearable smart heart monitor and view your recorded data. Trusted by world-class athletes across the globe, the Frontier X2/X3 is a chest-worn Smart Heart Monitor that provides in-depth real-time feedback on your heart health. It can monitor your: - Heart Health - Heart Rate - Heart Rate Variability (HRV) - Breathing Rate - Strain - Rhythms - Training Load - Calories - Stress, and a lot more. • Accurately record your activity like exercise, running, cycling, resting, sleeping, meditation, etc for up to 24hrs with comprehensive heart health insights. • Spot changes in your heart health with Rhythm and Strain. • Train in the right zone without distractions with real-time, personalized, and discreet vibration alerts. • Add health event tags to help you understand how lifestyle choices and behavior affect your health. • Seamlessly integrate with Bluetooth-enabled wearables and third-party devices such as GPS sports watches, bike computers, and more. • AI-enabled algorithms - Receive post-activity training insights, recommendations, and weekly goals. • Frontier X integrates with HealthKit to export your Frontier X activities into the Health app and to read heart rate and biometric data. • IP67 Waterproof up to 1.5 M • Battery: 14+ days of typical use Now get deeper insights and data with Frontier Premium Subscription*: Metabolic Profile Analytics: Track training intensity and the impact of lifestyle changes on metabolic health with key metrics like VO₂ Max, VO₂ Zones, Oxygen Uptake, and Ventilatory Thresholds (VTs). VO₂ Max: Get the most accurate real-time VO₂ Max data. While other wearables estimate using motion and heart rate, our advanced algorithms provides precise VO₂ Max readings outside of a lab, tracking cardiovascular efficiency and endurance potential. Readiness Score: Determine if your body is ready for peak performance or needs recovery. Advanced algorithms use heart rate, heart rate variability (HRV) to guide your daily activities and training. Sleep Stage Analysis: Get a comprehensive understanding of your sleep quality (Webapp). With Frontier's Premium subscription and Metabolic Profile Analysis, tracking your VO₂ max becomes simpler and more precise. *A Paid Frontier Premium subscription is required to access the full feature set . The Premium feature subscription comes with a complimentary 7 days free trial, and continue at a minimal monthly cost starting from USD 14.99, or opt for an annual plan for substantial savings. Please note that prices may fluctuate based on your geographical location, currency, and current exchange rates The Terms of use are available in the app and our website: https://in.fourthfrontier.com/pages/terms-of-use About Fourth Frontier Fourth Frontier is an innovative health-tech company focused on revolutionizing heart health monitoring with its cutting-edge wearable technology. We are the World’s First Smart Heart Monitor. With over 5 billion heartbeats recorded from 120,000+ users across 50+ countries, we are empowering users to understand and manage their heart health in real-time. These features make the Frontier App a comprehensive tool for heart health management and fitness improvement. Download the app today and access the most accurate heart health data available. Apps available for iPhone and Apple Watch.

About

PRO SKI Sensor

Features
Read full description

APP (compatible with any operating system) + Sensors in Boots + Audio (wifi communication) will tell you in real time, where points of the track your turns are or are not correct regardless of the state of the snow. APP (compatible with any operating system) + Sensors in Boots + Audio (wifi communication) will tell you in real time, where points of the track your turns are or are not correct regardless of the state of the snow. You will be able to overcome levels and evaluate the tracking of your performance in the moments of stops or at the end of the day with the summary of statistics either with your teacher or with your friends and in different formats. The map will show you the exact point of the track where you may have lost some of the symmetries or supports How's your technique? Real-time metrics. PRO SKI Academy Sensor talks to you at every moment about your turns, measure the angles between songs, necessary supports, and the parallelism of your skis. We are using Healthkit APIs To get the following data: 1. Height 2. weight 3. Age 4. Heart-Rate We are getting your Height, weight, Age. So, we can update your current profile data and "heart-rate" so while skiing we can show your current "hear-rate" to you. This will help you to track your health better.

Screenshots

Frontier X4 screens
PRO SKI Sensor4 screens

Verdict

The call

The clearest difference is price: Frontier X at Free against PRO SKI Sensor's $0.99. PRO SKI Sensor's advantage is in-app purchases (none vs 2). On update cadence, ads, device support and iOS requirement 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

Frontier X is free to download; PRO SKI Sensor costs $0.99 up front. Frontier X sells 2 in-app purchases, starting at $14.99 per month. PRO SKI Sensor asks for nothing beyond the download.

UpkeepUpdate frequency

Frontier X ships an update every 3 weeks, PRO SKI Sensor monthly. The most recent releases landed on October 12, 2026 and September 26, 2026 respectively.

Scorecard2 real differences · 8 level
Frontier X versus PRO SKI Sensor: the parameters behind the verdict, then further details
ParameterFrontier XPRO SKI Sensor
PriceFree — better$0.99
Rating4.6 (318 ratings) — better—
Positive reviews81.8% of reviews—
Number of ratings318 — better—
Update frequencyEvery 3 weeks — betterMonthly
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, Apple WatchiPhone, iPod
Requires iOS16.015.6 — better
Further details — not scored
Size569 MB102 MB
Age rating4+4+
DeveloperFourthfrontierPRO SENSOR DEVELOPMENT SL.

Bugs and requests

Frontier X

Reported bugs

4 issues
  • ECG stopped working
  • Inaccurate breathing rate and other metrics
  • Inability to edit activity details for indoor workouts
  • Syncing issues with Garmin devices after firmware updates

Requested features

6 requests
  • Add interval markers
  • Improve integration with Apple Fitness/Fitness+
  • Add support for ANT+
  • Improve compatibility with other fitness apps and devices
  • Add more customization options for workouts
Show 1 more
  • Improve data visualization and analysis tools

PRO SKI Sensor

Not enough reviews yet to summarise bugs or requests.

In-app purchases

2 purchases

Frontier X

Subscriptions2
  • Monthly7 Days trial$14.991 Month
  • Yearly7 Days trial$119.991 Year
None

PRO SKI Sensor

No in-app purchases

Questions

Is Frontier X free?
Frontier X is free to download, with in-app purchases available.
Is PRO SKI Sensor free?
PRO SKI Sensor costs $0.99, with no in-app purchases.
Do Frontier X or PRO SKI Sensor have ads?
Neither Frontier X nor PRO SKI Sensor shows ads.
Which is updated more often, Frontier X or PRO SKI Sensor?
Frontier X ships an update every 3 weeks, and PRO SKI Sensor monthly. Most recently, Frontier X was updated on October 12, 2026 and PRO SKI Sensor on September 26, 2026.

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