How an app for bad dates helps business owners protect their privacy

The Burner mobile app generates disposable phone numbers for calls, texts and voicemail.
Jeniece Pettitt | CNBC
The Burner mobile app generates disposable phone numbers for calls, texts and voicemail.

A "burner" phone may seem more "Breaking Bad" than "Shark Tank." But an app that mimics throw-away mobile phones has found a home in the boardroom.

When Greg Cohn co-founded Burner — an app that allows you to buy extra phone numbers for your regular mobile phone and "burn" them when you're done with them — he foresaw users downloading it to buy something on Craigslist, hand out to salespeople as a "spamline" or give out on Tinder.

"We thought that it would be heavily about dating, privacy conscious folks, young women dating online," said Cohn, formerly of Yahoo.

But it turns out it has been a hit in what Cohn calls "the daylight cases": The business community. It has been helping entrepreneurs take customer service calls off their personal cellphones, helping bands get feedback on songs, and even collecting RSVPs at conferences.

"I was looking at different options for a work number because my co-founder and I are really mobile," said Tara Tiger Brown, co-founder of start-up KitHub, which provides educational kits for science, technology, engineering, arts and mathematics (STEAM) curriculum. "Some of the other options out there were hard to use or weren't convenient. I tried Google Voice but it was on my computer and it was always an interruption."

Burner has recently upped its bets on business, offering integration with tools like Slack, Google Docs, Dropbox and SoundCloud. For small business owners, that means customers could text a service hotline and their queries could feed into a Slack chat or spreadsheet. Important voicemails from investors could be backed up to SoundCloud.

"Facebook Messenger wants to kill the phone number, but I'm not putting it on my resume or scheduling a meeting with my colleague on it," Cohn said. "So how do you get the phone number in the workflow? SMS is super relevant when you're meeting people, even professional contacts. People just sort of default to texting people you give your business card to these days."

To be sure, while Burner removes the "uncrossable line" of giving out your personal phone number to outside contacts, it doesn't solve the privacy issues of those worrying their boss will see their personal communications — a big concern for workers, according to research by the Society of Human Resource Management.

Still, Burner is one of several apps looking to build on the phone number the way that operating systems have expanded the reach of messaging apps. A similar app, Flyp, is one of the most popular apps featured on small business community platform Manta. In the future, Cohn said he sees professionals who often carry two separate phones for home and work, like attorneys, police officers and reporters, taking advantage of the privacy afforded by a semi-permanent phone number.

He already has one convert. Vocal venture capitalist Fred Wilson, who has written about the inconvenience of carrying multiple phones, recently asked conference attendees to text him (at a Burner number) their email addresses so he could send them updates.

"We're bridging a little bit of both worlds," Cohn said. "Everyone should practice safe text."

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."