RaceChrono is a popular phone-based data logging app. It's a great option if you don't have a dedicated data logger — your phone's GPS provides the telemetry LapBrain needs for corner analysis.

Export from RaceChrono

  1. Open your session in RaceChrono
  2. Tap the share icon
  3. Select Export as VBO (recommended) or Export as RCZ
  4. Upload the exported file through the LapBrain web app
tip

VBO format is preferred — it's a simple, reliable format that preserves all the data LapBrain needs.

Tips for best results

Phone GPS is less accurate than a dedicated data logger, but you can significantly improve results:

  • Mount your phone securely — a tank bag or handlebar clamp mount works well. Vibration and movement degrade GPS quality.
  • Use an external GPS receiver — Bluetooth receivers like the Dual XGPS or Garmin GLO provide much better accuracy (10 Hz vs. your phone's 1 Hz). This is the single biggest improvement you can make.
  • Start logging before your first lap — this gives RaceChrono (and LapBrain) time to establish GPS lock and identify the start/finish line accurately.
  • Keep the screen on — some phones reduce GPS polling when the screen is off.
note

Even with phone GPS, LapBrain can analyze your corners and provide coaching. The analysis may be less precise than with a dedicated logger, but the recommendations are still actionable. Many riders start with RaceChrono and upgrade to a dedicated logger later.

Supported formats

  • VBO — standard export format, recommended
  • RCZ — compressed format, also supported

What to do next

  1. Upload your first session — see Your First Session for what happens after upload.
  2. Consider an external GPS — if you're getting value from LapBrain with phone GPS, a $100 Bluetooth GPS receiver will dramatically improve data quality.