Drinking and driving is no laughing matter, but short of being totally plastered, knowing where our actual blood alcohol content stands is not always obvious. And that’s where Breathometer comes in. This compact, pocketable device sports a slide-out 3.5mm auxiliary plug that connects to your iOS or Android smartphone’s headphone jack, analyzing your blood’s alcohol level after a simple exhalation and letting you know when to wait it out or hand over your keys. It also features 1 click calling for dialing up a friend or local taxi service, optionally blocks drunk texting (at least if its 200k stretch goal is attained), and tracks your progress after repeated tests to ensure your blood alcohol level is going in the right direction – whichever that may be.

Learn more at Amazon – $40