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Home Mobile Apps (iOS) iPhone - CarScope


You want to know your car's braking distance, braking time, acceleration, speed, kinetic energy, maximum power, heading, altitude, lattitude and longitude then CarScope is the right iPhone application for you.



CarScope uses the GPS-Speed to compute the overall braking distance as well as braking time depending on the set street condition (dry, wet or snow).
Furthermore, it measures the acceleration in driving direction and the centrifugal acceleration.
If the car gross weight is configured then the application calculates the kinetic energy and maximum power.
As additional information the current heading, altitude, lattitude and longitude are displayed.

The app uses the GPS (Global Positioning System) to calculate the speed and position, which implies that it works only outside of buildings or tunnels. Furthermore, you need to allow the app to determine your location.

- GPS-Speed [km/h or mph]
- Braking Distance [m or ft.]
- Braking Time [s]
- Acceleration [g = 9.81m/s2] in driving direction (Symbol: ^) and perpendicular to the driving direction (Symbol: <>) also called centrifugal acceleration. A yellow text color indicates a deceleration.
- Maximum Acceleration -> Reset those values by clicking the "Reset"-Button
- Kinetic Energy [kJ]
- Max. Power [kWmax] -> The calculation is only valid if the car drives in a flat environment. Drag caused by friction (e.g. tires, head wind, etc.) or any other power losses are not part of the computation. Click the "Reset"-Button to set the value back to zero. Attention: The measurement and calculation of the approximation needs at least a max. power of 2s.
- Course/Heading -> Depending on the configuration and GPS availability the value shows the GPS-Course or Magnetic Heading (yellow text color)
- Location Data: Altitude (m or ft.), Lattitude and Longitude
- Configuration:
+ Units -> Select either Metric or US units
+ Car Weight [kg or lb.] -> Set the gross weight of your car to allow the calculation of the kinetic energy and maximum power. Attention: If you change the units then you need to adapt the weight!
+ GPS-Course or Magnetic Heading -> Decide whether the GPS-Course (if available) or Magnetic Heading is displayed

Invalid data are marked by a red text color whereas yellow text colors either indicate a deceleration or a magnetic heading value.

The following standard values are the basis for the computations:
- 1 second reaction time (a good average for the reaction on a sudden event)
- 8m/s2 max. deceleration on a dry tarmac road (depending on brakes, tires, etc.)
- 6m/s2 in case of a wet tarred road
- 3m/s2 if the street is snowy

To assure precise acceleration measurements it is important to align the device with the driving direction and to execute the below described calibration procedure.

Calibration Steps:
1.) The car must be placed on a flat street (no tilt)
1.) The device should be tilted between 0° (Upper Edge pointing into driving direction) and 90° (backside points into driving direction)
2.) The device must be aligned in a way that the sidewards tilt creates a centrifugal acceleration (<>) value of 0.0
3.) Click the "Cal."-Button and achnowledge the "Alert Window"

Keep in mind that the acceleration measurement bases on g's wereupon 1g equals 9.81m/s2. Any tilt of the car (e.g. driving up a mountain) already creates g's the driver has to endure.


This Software is provided "as-is", without any express or implied warranty.
In no event will the author be held liable for any damages arising from the use of this software.