If you use your phone for everything then maybe you will be in line to try the Breathometer app.
Basically, you get a small device that plugs into your phone, talks to the app and makes presto, you can breathe into it and get an alcohol reading. A reading that will be kept in a history of every time you blow into the device.
It will cost $20 which could get you a crappy, low-end breathalyzer test since most are in the $100 range.
Truth be told, I have seen people do weirder stuff with their phones.