If you frequent the bar, or just like to have the occasional drink, then a new iPhone application has Got Your Back.
As a matter of fact, that is the name of the application; except it is spelled BAC (as in Blood-Alcohol Concentration).
With this application you will know exactly when you should call a taxi.
When you first launch the application, you'll enter some personal information, like age, weight, and gender, so the application can calculate your BAC correctly.
The main display shows four drinks on a table.
You can change the type of beverage by double-tapping and selecting a different one - the icon will also change.
Each time you drink a beverage, you drag the icon off the table and onto the screen.
The BAC, Carbs, Calories, and number of drinks will be updated in the top-left corner of the screen. As you add drinks, these numbers will increase.
The red line across the screen indicates the legal limit - when you're above this line, a new button will appear called "call a taxi." When tapped, this button will launch the Maps app and search for taxis.
It would be useful if you could input a number for a designated driver, that way you don't have to fumble through your contacts or call a taxi.
OK, so it won't stop you drinking and driving but anything towards that goal I think is a good thing, and I speak from personal experience!
Got Your BAC is available from the Apple Store for $2.99 (US), or HERE
Remember, the best thing to do is to not drink and drive but if you are going to I encourage you to download and use this app - Christmas is a time for indulging, but at least do it safely.