Can Breathalyzer Phone Apps Tell Whether You Are Legally Drunk?

Breathalyzer Mobile AppsMore and more people are buying portable devices to test blood alcohol level. They’re small enough to fit in your pocket, and affordable, costing as little as $50. And they’re easy to use: plug them into your smartphone and blow to see your blood alcohol content on the spot.  The companies say these apps will help you make smart decisions. But police say they can be unreliable, and, in some cases, could lead to drunk driving.

NBC national investigative correspondent, Jeff Rossen looked at three such apps (Breathometer, Alcohoot, BACtrack Mobile) and compares them to official police Breathalyzers.

Social Experiment Scenairo

A summer barbecue and cocktail party was staged.  Along with the guests came New Jersey State Police, armed with the official Breathalyzer they use to arrest people who have blood alcohol content above the legal limit for adults of .08 percent.  Over the afternoon, one guest named LouAnn had six drinks.

Actual Police Breathalzyer Results

The police Breathalyzer showed she was drunk and would have been arrested if she had been driving: a reading of .175, more than twice the legal limit. “I can feel that I’m a definite risk,” LouAnn said.

App Results

Breathomater: 0.06 , under the legal limit for driving. Even LouAnn was surprised at the result. “Is there an app that says that’s [BS]?” she asked.

Alchohoot: 0 .16, twice the legal limit. Wildly different results from the previous app. “I think I agree,” LouAnn said.

BACtrack Mobile: 0.21, far over the legal limit, the highest result of the three apps. The third app, BACtrack Mobile, said she was even more drunk, the highest of all three.

Two additional party guests were tested. A table of results can be found below. The police Breathalyzer found all the partygoers who had had drinks over the limit: legally drunk. “I don’t know how you trust anything if you can’t trust one,” said one guest. “I’m very surprised they’re wildly different,” said another guest. “It’s crazy.”

The readings from all four devices:

Party Guest Official Police Findings Breathometer Phone App AlcohootPhone App BACtreack Mobile Phone App
LouAnn 0.175 0.06 0.162 0.21
Jeremy 0.119 0.05 0.107 0.143
Tali 0.08 0.07 0.078 0.1


The results from all three mobile apps were found to be all over the map. Alcohoot’s numbers were closest to the police Breathalyzer’s. The company called the results “impressive” and “consistent” with the police readings.  BACTrack’s numbers were too high. The company told NBC News its results showcase a “small margin of error” and they “erred on the side of caution and safety for the consumer.”  Breathometer’s results were way too low, showing all drinkers participating in the social experiment under the limit. The company said it was “surprised” by the results, and said: “Breathometer will be releasing an all-new Breathalyzer this fall — focused on law enforcement-grade accuracy.”  “Frankly, it confirms my suspicions,” said Mike Halfacre, director of New Jersey’s division of Alcohol Beverage Control (ABC), when he reviewed the results. “These things aren’t science; they’re party favors. They shouldn’t be relied on. They could put people on the road when they’re over the limit.”

“They have to be accurate,” LouAnn said. “There’s too much at stake.”  The companies say you shouldn’t use these apps to make a decision about whether you should drive: Those warnings are on the packaging and within the apps themselves.  But police worry that that’s exactly why customers will buy them: to see if they’re OK to drive. They say the best advice is: If you think you need a blood alcohol test, you should already know the answer — you shouldn’t drive, period.

Of course, no one should operate a motor vehicle after they have been drinking.  Hopefully, these apps will evolve to the point that they assist in determining whether you are over the legal limit.  Until then, it is better to be safe than sorry.  If you find yourself faced with a charge of driving under the influence/driving after imbibing, call our office at 610-945-9456.  We have successfully handled these types of cases in Montgomery, Bucks, Chester, Delaware, and Philadelphia counties for almost 30 years.

Posted on August 29, 2014, in Alcohol, Criminal Law, DUI, Minor, Underage Drinking and tagged , , , , . Bookmark the permalink. Comments Off on Can Breathalyzer Phone Apps Tell Whether You Are Legally Drunk?.

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