Your iPhone Is a Telemetry Box
Hot Laps uses your device's built-in accelerometer, gyroscope, GPS, and barometer to capture real-time performance data on track days, autocross events, and drag strips.
Race Mode
ProRecord full sessions with live lap timing, speed readout, and a real-time G-force ball. Set a GPS start/finish line and Hot Laps detects laps automatically. Watch your track outline draw itself on the mini map as you drive.
- Live lap timing with automatic lap detection
- Real-time speed readout and G-force ball
- GPS-based start/finish line
- Track outline drawn live on mini map
- Post-session review with speed traces and G-force charts
- Lap-by-lap breakdowns
Performance Tests
Put your car through its paces with straight-line and handling tests powered by your iPhone's built-in sensors.
Acceleration Test
Configurable 0-to-X targets (30, 45, 60, 80, 100 mph) with live G-force
Braking Test
ProConfigurable X-to-0 targets (30, 40, 60, 80, 100 mph) with time and distance
1/8-Mile & 1/4-Mile Drag
ProDistance-based acceleration with trap speed
Brake Fade
ProRepeated braking cycle analysis
Turning G
ProCornering force measurement
Roadmap
These tests are in development and will arrive in future updates.
More Features
Vehicle Garage
Manage multiple vehicles with full spec sheets. Log modifications with part numbers and costs. Track maintenance history. Built-in database auto-fills specs for thousands of year/make/model combinations.
Sensor Calibration
Guided calibration ensures accurate readings before every run. Mount your phone, hold steady, and the app locks in your device orientation using rotation matrix averaging with real-time stability feedback.
Session Analysis
Every session is saved with full telemetry. Review speed-over-distance graphs, G-force charts, elevation profiles, and track maps. Compare your best laps and track improvement over time.
Diagnostics
Live sensor dashboard shows the status of every data source — motion sensors at 50 Hz, GPS lock quality, barometer altitude, and data logging health.
No Extra Hardware
Everything runs on your iPhone's built-in sensors. No OBD dongles, no external GPS units, no additional equipment required.
Privacy First
All data stored locally on your iPhone. No accounts, no cloud uploads, no tracking. Your performance data stays completely private.
Simple Pricing
Free
- Acceleration test (configurable 0-to-X targets)
- Diagnostics dashboard
- One vehicle
- Most recent run per test
Pro
Intro price — increases to $4.99 in May
- Braking test (configurable X-to-0 targets)
- Race Mode with GPS lap detection
- 1/8-Mile & 1/4-Mile Drag
- Brake Fade & Turning G
- Session history
- Garage — unlimited vehicles & full run history
Your Data, Your Device
All data is stored locally on your iPhone. No accounts, no cloud uploads, no tracking.
- Everything stored locally on your device
- No accounts, no servers, no cloud uploads
- No tracking or analytics
- No third-party SDKs or ad networks
- Your performance data stays completely private
Ready to Hit the Track?
Hot Laps is coming soon to the App Store. Stay tuned.