It can happen that you’ve had one or two drinks and you think you are fine to drive…but the police may not agree with you. How to quickly find out if it’s safe for you to drive?

Thanks to your iPhone, and a 99-cent application called BreathalEyes, you can have functionalities similar to a breathalyzer on your smartphone.

The app can detect involuntary eye movement which is usually caused by alcohol consumption.
Using the iPhone’s camera, the application detects and analyzes Horizontal Gaze Nystagmus (HGN), BreathalEyes approximates a subject’s Blood Alcohol Content (BAC) with an effective range of 0.02% – 0.17% (+/- .02%) BAC.

Its developer warns that the results may not be always accurate because each person reacts differently to alcohol. The test results are for reference only and maybe affected by conditions such as high altitude and interaction with medications.

Nevertheless these 99-cent can save your arse from ending up in jail or people getting killed.

I haven’t tried the app yet because I don’t quite feel like getting drunk at 10 am!

BreathalEyes is available from the iTunes App Store and it’s only compatible with iPhone and iPod touch.