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Breathometer personal breathalyzer review: iPhone breathalyzer fun, but prone to mistesting

The Breathometer breathalyzer can be fun at parties, but its design makes it prone to improper testing

Wayne Cunningham Managing Editor / Roadshow
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
Wayne Cunningham
5 min read

The police use breathalyzers to test drivers' sobriety, so why shouldn't you have the same capability? That's the thinking behind the Breathometer, a personal breathalyzer device that determines your blood-alcohol level, showing if it's safe and legal to get behind the wheel after a night spent staring at rows of half empty bottles behind a bar or confessing your deepest desires to just-met strangers.


Breathometer personal breathalyzer

The Good

The <b>Breathometer</b>'s app interface makes it easy to start testing for blood-alcohol content. The color-coded graphic results also show at what time sobriety will be attained.

The Bad

The design of the device allows for mistesting and germ-sharing. The app does not let you share results on social networks.

The Bottom Line

The Breathometer makes for a fun party game and a potential way to meet people in bars, but its testing results should not be taken as proof of driver safety.

Actually, personal breathalyzers are not uncommon -- during a quick search on Amazon I found a variety, ranging from keyring-size to handheld models similar to the kind the police use. Breathometer's gimmick is that it turns your iPhone into a breathalyzer, putting a high-tech spin on drunkenness.

iPhone topper
The Breathometer device is small, about the size of an airplane bottle, making it easy to carry around in a pocket. A flap conceals a AAA battery, which provides enough power for 250 tests, according to the company's Web site. A hole through one corner makes it possible to attach a keychain. Another hole, near the opposite corner, glows like a bottle of Blue Curacao when the device is on. That's the breathalyzer part, where you blow out your rum-soaked breath and broken dreams.

A retractable 1/8-inch plug attaches the Breathometer to an iPhone's headphone jack. The Breathometer device seems designed for the iPhone 4 and earlier, where it will attach to the top-mounted headphone jack and line neatly up with the iPhone screen. The bottom-mounted headphone jack of the iPhone 5 makes for a clumsier fit with the Breathometer, and after the fifth Jack and coke users might find it difficult to piece the two together and use.

The Breathometer attaches an to iPhone's headphone jack. Josh Miller/CNET

Breathometer requires a free app be installed on its associated iPhone. Neither is much use without the other, just like gin and dry vermouth.

With the device attached to my iPhone, I found the app easy and intuitive to use. Once it recognized the hardware hook-up, the app showed a blue button large enough to defy double-vision. After running a test, the app displays results in equally large, color-coded graphics. Green meant I was clean and could easily read the .00 result shown in the middle of the circle. A yellow circle meant that the night was starting to get interesting, while red suggested driving would be a very bad idea, and that I had ceased to be the most fascinating person at the bar.

Popular at parties
Likely a comment on the quality of my friends, but when I pulled the Breathometer out at a bar, all were eager to give it a try. I had earlier attached it to my iPhone, launched the app, and breathed, as the app suggested, for five seconds into the glowing, blue ring. The result, .00 and green, proved the baseline accuracy and hinted at a lack of real spice in my life.

After a whiskey and a beer chaser, I waited Breathometer's suggested 20 minutes and gave it a blow. The result, .03 and a warning yellow ring seemed to comport with my alcohol intake. A friend who got an earlier start gave it a run, blowing a .06, again seeming to be in line with the amount of drinks drunk.

The resulting data includes what time you would be sober if you stopped drinking then and there. At .06, according to Breathometer, it would require four hours of sitting around and realizing that your drunk friends are all rather boring before the demon alcohol had left your system.

The Activity menu item shows your history of drunkenness. Screenshot by Wayne Cunningham/CNET

On its Web site, Breathometer asserts that it is FDA-registered and boasts an accuracy of plus or minus 0.01 percent blood-alcohol content at 0.02 percent blood-alcohol content.

However, knowing how I was supposed to use it, I figured out how to trick the Breathometer as well to show a high blood-alcohol content. Being that it was the middle of the day and I didn't want everyone around the office to smell booze on my breath, I got CNET's product photographer, Josh Miller, to take a swig of Irish whiskey, swish it around in his mouth, then forcefully blow into the Breathometer.

The result was an impressive red ring and .20 alcohol content, meaning he was technically dead.

Further in my extensive testing of Breathometer, I gave it a try after about five drinks, just when I was starting to lose count, and got a .05 result. I was actually feeling pretty buzzed at that point, and wouldn't have gotten behind the wheel even though Breathometer said I was legal. I suspected that I didn't breathe enough of my alcohol-sodden breath into it during the testing, but there was no alert from the device to suggest it had not gotten a good reading.

As Breathometer does not have a replaceable, sterile plastic nozzle in its breathing hole, as professional breathalyzers do, germophobes will shy away from taking part in the testing, especially after seeing the device covered in the breath, perspiration, and saliva of the crowd down the bar.

The Breathometer app offers options, such as a list of local cab companies sourced from Yelp. Screenshot by Wayne Cunningham/CNET

If you're relatively sober, you can find the menu icon in the upper corner and discover a few more options available in the app. The Activity item brings up a history of test results, so you can relive that night you got epically drunk. The Call a Cab menu item uses your location to bring up a list of cab companies from Yelp. When I tried this option in San Francisco, it showed five results for cab companies I had never heard of. I assume it merely grabs the first five from Yelp's search results. It would do better to show the five top-rated cab companies.

I was a bit disappointed with the Tell a Friend menu item. It gave me options for sending a text or an e-mail, or posting to Facebook. I expected it would let me impress my friends and disappoint my family by sharing my scientifically confirmed inebriation with the world. Instead, it merely worked as a marketing tool for Breathometer, recommending this wonderful device to all and sundry.

No proof of sobriety
At $49, the Breathometer rings up a bit higher than many stand-alone breathalyzers but comes in substantially cheaper than the only other smartphone-connected breathalyzer CNET has looked at, the BACtrack. The BACtrack is a larger device, but it includes replaceable nozzles to prevent germ-sharing and can post results to social media.

Because the Breathometer's design does not ensure uniform testing, I would not recommend it as a means of determining if you are safe to drive. More inebriated folks tend to lose some hand-eye coordination, so are less likely to breathe directly into the Breathometer device, skewing the results.

However, it proved very popular when I showed it to a number of alcohol enthusiasts. As a party piece, it is a fun conversation starter and should also get people thinking about the dangers of drunk driving.