G-Box Dyno

Measure acceleration, estimate power and torque, compare runs, and add synchronized telemetry to driving videos using iPhone, OBD-II or an external GPS receiver.

G-Box Dyno turns your iPhone into a focused vehicle-performance measurement tool.

Measure 0-60, 0-100, 0-160, 0-200, 80-120 and 100-200 acceleration. Run a single-gear Dyno pull to estimate power and torque, save high-rate telemetry, and compare repeat runs on clear graphs.

CHOOSE THE BEST SENSOR SOURCE

Use iPhone GPS and motion sensors, a compatible Bluetooth or Wi-Fi OBD-II adapter, or an external GPS receiver. G-Box Dyno automatically prioritizes a connected high-rate source and records source quality with every run.

BUILT FOR REPEATABLE TESTING

• Vehicle profiles with mass and gear calibration
• Power and torque curves versus engine RPM
• Automatic shift detection and useful run trimming
• Atmospheric data for consistent comparisons
• CSV telemetry and saved run history
• Portrait and landscape analysis views
• Optional rear-camera video with synchronized acceleration overlays

FREE TO START

Create one vehicle and complete three measurements with the standard 0-60 and 0-100 presets. Upgrade once to G-Box Dyno Pro for unlimited measurements, vehicles, advanced acceleration ranges, comparisons and video overlays. No subscription. No ads.

SAFETY AND MEASUREMENT NOTICE

Use only on a closed course or private road where legal. Configure the app while parked, mount iPhone securely, and never interact with the screen while driving. Performance results are estimates and are not certified dynamometer measurements. Accuracy depends on sensor quality, calibration, vehicle data, road grade, traction and weather.