Want to Know if You’re Sober Enough to Drive? Don’t Ask an App

Put “alcohol” and “apps” into Google and you’ll get dozens of possible downloads for your smartphone. Many are specifically aimed at helping you track your blood alcohol content (BAC), and each works pretty much the same way: You key in info every time you have a cocktail, and the app then uses that to track your BAC and gauges your fitness to drive. It’s just an app, though, and in many cases these tools don’t know how much you weigh; if you’ve taken medication; or even if you’ve eaten recently or had water—all of which affect your BAC.