To turn your Android phone into an ultimate fitness tracker, follow these steps using the available built-in sensors and recommended apps:

  1. Calorie Counting: Use MyFitnessPal to track your daily calorie intake, nutritional breakdown, and set weight loss goals.

    • Install MyFitnessPal from the Google Play Store.
  2. Fitness Tracking: Choose between Strava and Moves for tracking your activities.

    • Strava: Free, with social features and competitive segments.
      • Install Strava from the Google Play Store.
    • Moves: Free, background tracking with a simple timeline.
      • Install Moves from the Google Play Store.
  3. Heart Rate Monitoring: If your phone doesn't have a built-in heart rate monitor, use Instant Heart Rate to measure your heart rate using the camera sensor.

    • Install Instant Heart Rate from the Google Play Store.
  4. BMI Calculator: Calculate your body mass index to understand your body composition and adjust your fitness goals accordingly.

    • Install a BMI calculator app from the Google Play Store.
  5. Running Programs: Start a running routine with the Couch to 5K app.

    • Install Couch to 5K or similar apps from the Google Play Store.
  6. Connect to Accessories: If you want more precise data, consider using a Bluetooth heart rate monitor with compatible apps like Strava, RunKeeper, or SleepRate (iOS only).

  7. Sync with Other Devices: If you have other devices or a smartwatch, consider using apps that sync across platforms for a more comprehensive fitness tracking experience.

Remember, these apps and sensors will leverage your phone's built-in GPS, accelerometer, gyroscope, and in some cases, an optical heart rate monitor, to provide you with a robust fitness tracking experience.