How It Works
Everything you need to know to get started with Total Traction
Quick Start Guide
Get up and running in less than 2 minutes
Download & Install
Get Total Traction from the App Store and install it on your iPhone (iOS 15.0 or later required).
Mount Your Phone
Securely mount your iPhone in your vehicle. A dashboard or windshield mount works great. Ensure it's stable and won't move during driving.
Calibrate (10 seconds)
Park on level ground, open the app, and tap "Calibrate". Keep the vehicle stationary for 10 seconds. The app will automatically determine the gravity vector.
Select Road Condition
Choose the appropriate condition: Dry, Wet, Snow, or Ice. This sets the maximum traction coefficient for accurate percentage calculations.
Start Driving
You're all set! The app now shows real-time traction percentage with audio alerts. Practice smooth inputs and learn your vehicle's limits.
Understanding the Display
Main display interface
What You're Seeing
Traction Percentage (Center)
The large number shows how much of your available tire grip you're currently using. 0% = stationary or straight line, 100% = at the limit of adhesion.
Vector Arrow (Vector Mode)
Shows the direction and magnitude of lateral forces. Points in the direction your body feels pushed during maneuvers.
Concentric Rings
Visual guides at 75%, 50%, and 25% of maximum traction. Help you quickly gauge how close you are to limits.
Color Coding
Green (0-75%) = Safe zone
Yellow (75-90%) = Caution zone
Red (90-100%+) = At limit
Condition Indicator
Shows your current road condition setting (Dry, Wet, Snow, Ice). Tap to change.
Training Mode: Practice Makes Perfect
How to use Total Traction as a training tool
Winter Driving Practice
Goal: Build muscle memory for icy conditions
- Find an empty parking lot on dry pavement
- Set app to "Ice" mode (0.15g threshold)
- Try to drive around without triggering audio alerts
- Practice smooth throttle, brake, and steering inputs
- Gradually increase speed while maintaining silence
Smooth Driving Skills
Goal: Eliminate jerky inputs and improve passenger comfort
- Use "Dry" or "Wet" mode on actual roads
- Set audio threshold to 60-70%
- Drive your normal route
- Listen for audio feedback during corners and stops
- Practice making inputs smoother when alerts trigger
Performance Driving
Goal: Learn to use more of your vehicle's capability
- Use at a track day or autocross event
- Set to "Dry" mode with threshold at 85-90%
- Monitor consistency lap-to-lap
- Identify corners where you're leaving performance on the table
- Gradually increase cornering speeds while watching percentage
The Physics Behind Total Traction
Understanding what the app measures and calculates
1. Gravity Vector Detection
During calibration, the app measures the gravity vector while your vehicle is stationary. This tells us "down" regardless of how your phone is mounted.
2. Force Decomposition
While driving, the app separates total acceleration into two components:
- Parallel (Normal Force): How hard the road pushes up on the tires
- Orthogonal (Lateral Force): Sideways forces from cornering, braking, accelerating
3. Available Traction Calculation
Maximum traction = μ × N, where:
- μ (mu) = Road condition coefficient (0.15 for ice, 0.85 for dry)
- N = Normal force (changes with banking, hills, compression)
4. Dynamic Adjustment
The app continuously recalculates available traction based on road geometry:
- Banking increases N → more traction available
- Hill crests decrease N → less traction available
- Dips/compression increase N → more traction available
5. Percentage Display
Current lateral force ÷ Available traction × 100 = Your traction percentage
This gives you meaningful feedback regardless of conditions, unlike raw G-force numbers.
6. 60Hz Updates
All calculations happen 60 times per second for real-time feedback that matches what you feel through the steering wheel and seat.
Tips for Best Results
Phone Mounting
Use a secure mount that won't move during driving. Dashboard or windshield mounts work best. Ensure good visibility without blocking your view.
Calibration
Always calibrate on level ground. If you change your phone mount position or orientation, recalibrate. Takes only 10 seconds.
Condition Selection
Be conservative when selecting road conditions. If it's recently rained, use Wet mode even if roads look dry. Surface water isn't always visible.
Audio Settings
Adjust threshold based on your goals. Lower threshold (60-70%) for learning smoothness. Higher threshold (85-90%) for performance driving.
Tire Condition
The app assumes good tire condition. If your tires are worn or damaged, available traction will be lower than indicated. Drive accordingly.
Learning Curve
Start with gentle maneuvers and gradually increase intensity. Focus on consistency before pushing limits. Smooth is fast.
Understanding Common Maneuvers
Cornering
What you'll see: Vector points to the outside of the turn. Percentage increases with speed and tightness of the corner.
What it means: You're using lateral traction to change direction. Higher percentage = tighter or faster corner.
Training tip: Try to keep percentage below 70% for smooth, passenger-friendly cornering.
Braking
What you'll see: Vector points forward (direction of inertia). Percentage increases with braking force.
What it means: You're using longitudinal traction to slow down. This is correct physics—inertia pushes you forward when braking.
Training tip: Smooth, progressive braking keeps percentage lower than sudden stops.
Acceleration
What you'll see: Vector points backward. Percentage increases with throttle application.
What it means: You're using longitudinal traction to speed up (inertia pushes you back in your seat).
Training tip: Gradual throttle application, especially in low-traction conditions, keeps percentage manageable.
Trail Braking
What you'll see: Vector points forward and to the outside. Percentage higher than cornering alone.
What it means: You're using traction for both slowing and turning. Advanced technique—be careful not to exceed 100%.
Training tip: Practice in safe environments. This technique is for experienced drivers on track.
Common Questions
Quick answers to frequent questions
Why does the vector point forward when I brake?
This is correct physics! When you brake, inertia pushes you forward (you feel it in your seatbelt). The app shows the inertial forces, not the braking forces. Think of it as showing what your body feels.
Can I use this on a motorcycle?
Yes! As long as you can securely mount your iPhone, Total Traction works on any vehicle. The physics are the same for cars, trucks, and motorcycles.
Do I need to recalibrate every time?
No. Calibration persists between app launches. Only recalibrate if you change your phone mount position or orientation.
Does it work with CarPlay?
Audio alerts work through CarPlay, but the visual display doesn't (Apple restriction). Mount your phone where you can see it, and audio will route to your car speakers automatically.
Ready to Get Started?
Download Total Traction and start improving your driving today.