Automotive App of the Week: iAutomotive

When basic vehicle diagnostic information such as rpm and oil pressure are not enough, the iAutomotive iPhone app lets hard-core car enthusiasts drill down into more esoteric performance indicators such as drag coefficient and wheel vs. flywheel power. And if you've ever wondered how your vehicle's performance could be improved by tweaking such variables as weight and driving speeds, iAutomotive could be the best $1.99 you've ever spent.

When you're first setting up the app, you tap the Units button to enter parameters and such preferences as flywheel power or power at the wheels, km/h or mph and kilograms or pounds for vehicle weight. Once you have set your preferred units, you enter your own vehicle's specifications.

We thought it would be more fun to check the specs on a Bugatti Veyron rather than the editor's own Chevy Blazer. So we used the Bugatti numbers provided in an example section that the app manufacturer offers to calculate how we could operate our mythical Bugatti more efficiently.

Calculating Vehicle Dynamics
Whether you choose a fantasy ride or your everyday commuter, you're now on your way to calculating vehicle dynamics using factors including Frontal Area (measuring the effect of add-ons like spoilers and surf racks), Drag Coefficient (the effect of driving a convertible, for example), Power (to tune or not to tune), Speed and Weight. And in a nod to driving efficiency, the app has an "MPG Calculations" button that computes mileage data based on factors you customize. Settings include manual or automatic, rear-wheel or front-wheel drive, 4x4 or motorbike.

A cool element is that when you're ready to input required data fields, such as Drag Coefficient, the app provides an information button to help you come up with the correct numbers. Tap the "i" button next to Frontal Area, for example, and the app gives you several options ranging from using Photoshop-like grids to an Internet search to assist you in gauging this vehicle variable.

Grab and Save Data
Yet another handy tool in iAutomotive is the ability to do screen grabs and save your data. From the main screen, tap the "Log Screen" button to show your results. Here you will get five columns of data including Area, Drag, Power, Speed and Weight. Simultaneously press the "Home" button and click the sleep/wake key on top of your iPhone, and your device will capture an image and save it to your photos folder.

But we found one area where the app itself could use a tune-up: iAutomotive occasionally froze when we were navigating the buttons using an iPhone 3GS. Otherwise, it's a pretty powerful automotive tool for less than 2 bucks.