What is a fitness tracker?
A fitness tracker is a wearable device — typically a wristband, watch or ring — that monitors your physical activity, heart rate, sleep and other health metrics. It collects data continuously and syncs it to an app on your phone, where you can view trends and insights.
Prefer tracking with just your phone?
Trakon uses your phone's GPS and sensors — no wearable needed. Free on iOS and Android.
What sensors do fitness trackers use?
| Sensor | What it measures |
|---|---|
| Accelerometer | Movement, steps, activity type |
| Gyroscope | Rotation, orientation |
| Optical heart rate | Heart rate via light on the skin |
| GPS (some models) | Location, distance, pace, route |
| SpO2 sensor | Blood oxygen levels |
| Skin temperature | Body temperature trends |
| Altimeter | Elevation, floors climbed |
What do fitness trackers measure?
- Steps — daily step count using accelerometer
- Heart rate — continuous or on-demand via optical sensor
- Sleep — duration and quality based on movement and heart rate
- Distance — estimated from steps or GPS
- Calories burned — estimated from activity, heart rate and body data
- Workouts — running, cycling, swimming, strength training
- Stress — some models estimate stress from heart rate variability
Track activities and nutrition in one app.
Trakon combines GPS activity tracking with AI food scanning — no separate fitness tracker needed.
Types of fitness trackers
Wristbands (e.g., Fitbit, Xiaomi Mi Band)
Basic fitness tracking at a low price. Good for steps, heart rate and sleep. Limited smart features.
Smartwatches (e.g., Apple Watch, Garmin, Samsung Galaxy Watch)
Full fitness tracking plus smart features — notifications, apps, music, payments. More expensive but more capable.
Smart rings (e.g., Oura)
Focus on sleep, recovery and heart rate. Discreet but limited workout tracking.
Phone-based tracking (e.g., Trakon)
Uses your phone's built-in GPS and sensors. No extra device to buy or charge. Great for GPS activities like walking, running and cycling.
Do you need a fitness tracker?
It depends on your goals. If you want to track walks, runs and bike rides, a phone-based app like Trakon is sufficient. If you want 24/7 heart rate monitoring, sleep tracking and step counting without your phone, a wearable is worth considering.
Read our full analysis: Do You Really Need a Fitness Tracker to Get Fit?
Start tracking for free — no wearable required.
Download Trakon and track your first walk, run or bike ride today.
Read next: Best Fitness Tracker Apps in 2026