GTrace - G-Meter & Logger
G-force traces for track days
Only for iPhone
USD 0.99
iPhone
Your cornering, braking and throttle drawn as a live G trace, replayed against the map or your own footage afterwards.
Track day or mountain road, every G you used stays on record.
GTrace turns your iPhone into a real G-meter. It draws the lateral and longitudinal G-forces from your cornering, braking and throttle as a live trace, then lets you replay the run against the map, your footage or the graphs.
One-time purchase. No subscription, no in-app purchases.
WHILE YOU DRIVE
- Live G-G diagram, lateral and longitudinal G shown together
- Trailing trace, with peak lateral and longitudinal G held on screen
- Jerk shown as a crosshair, so you can see how smoothly you transfer load
- Speed readout, switchable between km/h and mph
- Audible alert when you exceed your chosen G threshold
- Comfort and Sport modes with separate display ranges for street and track
- Three display layouts: standard, info + speed, and video preview
- Phone holder mode, so a vertically mounted phone still reads longitudinal G correctly
MEASUREMENT
- Gravity component removed to isolate true vehicle acceleration
- 2nd-order Butterworth IIR low-pass filter with adjustable cutoff frequency
- Configurable sampling rate
- Axis inversion, so mounting orientation doesn't matter
AFTER THE RUN
- G-G heat map showing which part of the friction circle you actually used, so you can see the balance between cornering, braking and acceleration at a glance
- Synced playback: G-G + map, G-G + video, G-G + acceleration graph, or map + graph, at adjustable playback speed
- Time-series graphs for longitudinal G, lateral G, longitudinal jerk, lateral jerk and speed
- GPS trace drawn on a map, with top and average speed
RECORD AND SHARE
- Voice recording, synced to the acceleration data for commentary and notes
- Video recording with audio, played back with the G-G trace overlaid
- CSV export for spreadsheets or your own analysis tools
- Native binary format (.ggx) import and export, for backups and moving data between devices
WHO IT'S FOR
- Track day, sports driving and time attack enthusiasts
- Drivers working on their technique on mountain roads
- Anyone chasing smoother, more passenger-friendly load transfer
- Motorsport competitors who want their practice data kept
- Anyone who wants their car's behaviour in numbers
English and Japanese. iPhone only, iOS 15.6 or later.
Note: measurements use the iPhone's built-in accelerometer and gyroscope. Mount the phone firmly in the vehicle for accurate readings.
Note: GPS trace and speed recording require location permission.
Note: this app does not include lap timing.
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
The app is now called GTrace, previously G-G Diagram. All features and your saved recordings are unchanged.
- Japanese is now listed as a supported language
- Unified the app name across the app and the App Store
The developer, YUJI IKEDA, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- YUJI IKEDA
- Size
- 41.1 MB
- Category
- Navigation
- Compatibility
Requires iOS 15.6 or later.
- iPhone
Requires iOS 15.6 or later.
- iPhone
- Location
- This app may use your location even when it is not open, which can decrease device battery life.
- Languages
- English and Japanese
- Age Rating
4+
- 4+
- Copyright
- © Yuji Ikeda
