If the reports are to be believed and Garmin (and by extension the rest of the GPS market) is having a hard time selling portable navigation devices, then we're sure that its EcoRoute HD add-on modules aren't flying off the shelves. But Garmin is making the device useful to a whole new market of potential users--namely, Android fans--with the release of its Garmin Mechanic app for Android.

We'll cut to the chase: if you already own a Garmin EcoRoute HD, the Garmin Mechanic app for Android is free application that allows you to take advantage of the data provided by your car's onboard diagnostics port (OBD) to view and log very accurate fuel economy information, engine operating parameters, and trouble codes. It is very cool. However, we're sure that most people don't have an EcoRoute HD just lying around, so for the rest of you, the Garmin Mechanic app is a useful app that requires a $100 piece of hardware to operate effectively, which makes it, essentially, a $100 app--which is not so cool and a much harder sell. We prefer to see the glass as half full, so we'll be taking a look at the Garmin Mechanic app for Android from the former of the two perspectives. We took the app for a spin in a variety of vehicles to see how it handled.