StopOMeter - The New Driver iPhone App. StopOMter - The new driver stopping distance iPhone app.
 Advancing New Driver Safety
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StopOMeter - new driver stopping distance / speed app. Installation

Failure to avoid the following potentially hazardous situations could result in an accident or collision resulting in death or injury.

When installing the iPhone in a vehicle, place the unit securely so it does not
obscure the driver's view of the road or interfere with the vehicle operating
controls such as the steering wheel, foot pedals or gear change levers. Do not place in front of or above any airbag.

It is advisable to ensure that the iPhone is plugged into a suitable power supply
within the vehicle as the app will drain the iPhone's battery quite fast when using
its features.

Always operate the vehicle in a safe manner. Do not become distracted by the
iPhone or the app whilst driving and always be fully aware of all driving conditions.


The iPhone should be mounted securely into the vehicle preferably by use of a purpose built iPhone dock.
Details of suitable docks can be found on the Car Mounts page of the website.

It is preferable to mount the iPhone upright in a purpose built docking cradle, but with the HUD option you can
also mount the iPhone flat on top of the dashboard. There are a number of ‘Bean Bag’ type mats that can help keep the iPhone in place.

Care should be taken to ensure that the iPhone has the clearest possible view of the sky so that  the GPS unit
can read the maximum number of satellites.


The accelerometers at the heart of the Stop-O-Meter app need to be calibrated before use otherwise you
might get spurious results.

The raw iPhone accelerometer values can show an error of up to 10% which can be corrected for by selecting Information > Calibration.

The calibration screen consists of three bars, with superimposed accelerometer values. Each bar has a contrasting centre stripe which indicates the amount of variation for the current calibration settings.

If the iPhone has not been calibrated, then Not Calibrated will be displayed at the bottom of the screen.

To begin calibration, find a flat surface to work on and press the [Calibrate] button and select Calibrate from
the pop-up menu. A large arrow will appear on the screen. Orientate the iPhone on the edge indicated by the arrow and move it so it is vertical. Once the local vertical has been sensed for that edge, you will hear a beep
and the next large arrow will be displayed pointing to the next edge to be sensed. The order of sensing is left edge, right edge, bottom edge, top edge, screen up and finally screen down. The display will change to give
you the date and time of the calibration. You will notice that the contrasting bars are no longer aligned with the main bar, which indicates the degree of error found in the accelerometers.

Orientation to the Vehicle.

To orientate the iPhone to the vehicle, first stop the car on a flat piece of tarmac such as a car-park etc.

From the main screen touch the Centre button. (Using this option does not perform fundamental calibration of
the unit accelerometers, it is simply there to re-orientate the iPhone each time it is moved from its dock or cradle).

The Stop-O-Meter is ready for use when the blue dot is centred in the oval window of the Eco Driving indicator.

How the stopping distances and times are calculated.

The Stop-O-Meter indications are based on the Stopping distance and times table that is published in the
Highway Code. These are optimum times and distances and assume that the road surface is dry and in good condition, the driver is fit and alert and the car is in a good state of repair.

It is highly recommended that new drivers seek out a driving Instructor that has our Driving Instructor app and
go and do some concerted practice at emergency stops. The Driving Instructor app gives a complete graphical overview of a drivers braking performance and is particularly useful for new drivers as well as those learning to drive. If your Instructor does not have the app, then it can be obtained through the app store.
Go to for more information.
User Interface        Rules For Use        Stop Horizon        2 Second Rule        Eco Driving        Help        Contact