Person A: "Man, I was so wasted last night..."
Person B: "Oh really? Well, exactly how wasted were you? What hard data do you have to back up this outrageous statement, sir? I demand satisfaction!"

With BACtrack's new Mobile Breathalyzer, you can finally gain the upper-hand in this unlikely, imaginary argument.


It's Friday afternoon, you've made it through the long week, and it's time for Happy Hour, Gizmodo's weekly booze column. A cocktail shaker full of innovation, science, and alcohol. But how much alcohol, precisely?

What Is It?

It's a tiny and lightweight breathalyzer that pairs with your smartphone, and gives you not only your current blood-alcohol content (BAC), but also a projection of your time to sobriety, and a chart of your own drunkenness.


Why Does It Matter?

Well, it could save a friend's life. Everybody has that idiot friend who claims to be "fine to drive" when he or she definitely is not. Showing them just how over the legal limit they are might convince them to wait or take a cab. Hopefully. It also matters because it's so small, and because it's the first breathalyzer that pairs with a smartphone, as far as we know.



It's freakin' adorable! At only 1.75 x 2.75 x 0.63 inches and 1.7 ounces, you could forget you have it in pocket of your tight hipster jeans. Hell, it fits in the little fifth pocket. That means you're more likely to actually take it with you.

The body itself is plastic. It has just one button (on/off), and a little plastic tube at the top. The real magic is what's inside, though. The Mobile Breathalyzer uses an Xtend™ Fuel Cell Sensor, which is the same technology used by police and hospitals. It can detect even trace amounts of alcohol, down to 0.001 percent. It's the pro-grade sensor, basically.


There is no display on the device itself—all of the info comes to you through the smartphone app. It uses Bluetooth 4.0, making it compatible with iPhones after the 4S, iPads after the 3, and Android phones running 4.3 and up (and Samsung phones beyond the Galaxy S3). It charges via mini USB, and it comes with three washable, reusable mouth-pieces, should you fear the cooties.

Using It

It's pretty dang easy to use. Simply download the app for iOS or Android, open it, then turn on the device. It will have you pair the phone and BACtrack with a single click, then click a second time to test. It gives you about 10 seconds to get ready, then you blow into the device for five seconds. It clicks, and you're done.


After taking a few moments to calculate your results, it brings you to a page where it says in big bold letters what your BAC is, and it estimates what the effects you're feeling are. Go to the next page, and you get into the more serious data. Most significantly, it gives you an estimated timeline for how long it will take you to get back down to 0.0 percent. There are also options for mapping where you are, taking photos and notes on what you just drank, and and saving your results. You don't have to do any of that stuff, but you've got the option, should you want it.

There's also the option of sharing your results privately (via text message) or more publicly (via social media). The private sharing make some sense, if you're hoping a friend will pick you up and you're too lazy or trashed to write it out via text message. The social element seems dangerous, though, and could lead to idiots trying to blow the highest BAC percentage to outdo each other.


The one annoying thing is that you have to wait 15 minutes after your last drink before you test. That's not specific to this product, but to all breathalyzers in general. If you test within 15 minutes of a drink your results will be higher. It's hard to be patient when you want to find out how drunk you are now.


It's really fun. Every time I've pulled it out in a bar, all of my friends wanted to try it (you might want to get some straws, for sanitation's sake). It also started interesting conversations. People were always really surprised at how long it takes for the alcohol to be completely out of their system. A friend's dad lives in the mountains and has a lot of parties. He takes everyone's car keys at the beginning of the night and won't give them back until they're well under the legal limit (0.08 percent BAC). I thought that was a great use-case.


Battery life is terrific. I charged it once, and have since done probably 60 or 70 tests, and it hasn't run out yet. I also love the tiny little form-factor of the device itself. The app is nicely laid out, easy to understand, and packs in a lot of information. We weren't able to test it next to a police breathalyzer, but the results were very consistent and, for what it's worth, everyone who tried it said, "Yeah, that seems about right."

Also, we had fun trying to game the system. My friend managed to blow a 0.344-percent BAC (see above image, on the left), which should have rendered her, as the app notes, unconscious. Luckily, she wasn't. In fact, she'd only had one drink, but rather than waiting 15 minutes after her whiskey, she tested her self almost immediately accurate. Good times.

No Like

There are some important things you need to understand about this thing (and all breathalyzers in general). For starters, just because you're under 0.08 percent (the legal limit for people over 21 in most states) does not mean that you should be driving, and it doesn't mean that the cops can't give you a DUI. They can, and that will suck. Don't use this thing as a crutch.


As for this device, specifically, the biggest downside is the price. At $150, it ain't cheap. Yes, they used the same high-grade sensors that they put into their S80 Professional Edition, but you can get the S80 for 40 bucks less. It's just not as portable and isn't app-capable.

It would be nice if the app showed not just when you would be down to 0.0 percent, but also 0.08-percent, for those who would want to know. We wish it was compatible with more Android devices, and it will be, as Android phones steadily get upgraded to 4.3 and beyond. But, for right now, it's a bit limited. It worked fine with a Nexus 5, but not at all with Verizon's Droid Maxx. Lastly, the plastic scratches fairly easily, as you can see in the photos.


Should You Buy It?

If it's important enough to you to have pro-grade results and you really want the app connectivity for all of the extra features (like countdown to sobriety), and you don't mind spending $150 for it, then yes. It's a pretty excellent product, and it works as advertised.


However, if you're more into the novelty of it and care less about absolute accuracy, you can get BACtrack's also-tiny Keychain Breathalyzer for just $30. That's a much easier pill to swallow, but it can only estimate to the nearest 100th of a percent, not 1000th of a percent like the Mobile can.

Overall, we liked this thing a lot. We just think it's overpriced. [BACtrack]