Employees like it because they can finally ditch their ancient BlackBerry. Companies like it because, half the time, employees end up paying for the data plan. Another perk, said one investment bank user: It's easier to update a new app by downloading it than to update a new device by going out and purchasing it.
CEO Christy Wyatt, who took the helm at Good in January after stints at Citigroup, Apple, Motorola and Palm, says she's seen an explosion in inbound calls from company executives who are at "an inflection point" and ready to make a change.
(Read more: Exit light burns bright at BlackBerry)
"For a long time, we've seen users carrying around multiple devices," Wyatt said in an interview with CNBC—noting one device is company-issued and the other is personal. "Increasingly, we see users being able to converge those two."
And—increasingly—Good's on the winning end.
In the last three quarters, the company's user base has grown 50 percent, Wyatt said, with a noticeable uptick in revenues in just the last 30 days. The reasons: an uncertain future for BlackBerry amid failed product launches, executive resignations and a failed takeover bid.
(Read more: BlackBerry replaces CFO as other execs hit the exit)
Founded in 1996, Good is a relative dinosaur in the mercurial tech landscape and an unlikely winner from BlackBerry's fall from grace. Motorola bought Good in 2006 for $400 million in an attempt to compete against then-Research in Motion "head on," before selling Good for a fraction of that price two years later.
Wyatt, then an executive at Motorola, is aware of the irony.
"Times were very different," the native Canadian said with a slight laugh, pointing out that BlackBerry's market share was about 20 percent. (It is now 1.8 percent, according to Gartner.) "If you would have asked me back then … I don't know that I would have been able to tell you about the phenomenon we're seeing now."
Now, Wyatt and her team are resurrecting the not-so-subtle goal to challenge BlackBerry.
The company hosts bi-weekly webinars on how companies can switch and is having a conference on the topic in Washington in early December. If that's not enough, it took out a full-page spread in the Wall Street Journal, suggesting companies start looking for an "exit strategy."
BlackBerry is only one of Good's competitors. Others—like the established Citrix, as well as startups AirWatch and MobileIron—offer similar connections between an array of devices and a company's servers (where emails, documents, and other desktop functions are stored).
(Read more: Apple vs. Microsoft: The battle for the office heats up)
In September, Good 's applications (which transmit 280 trillion bytes of data each year) were awarded the highest security certification possible, giving it yet another leg up on competition as it expands a corporate client base in search of the utmost privacy.
"You need to be able to do business from anywhere, securely," Wyatt said.
As the company continues to expand, it may seek to raise more capital in the process. Good brought on a new chief financial officer in October as it prepares for an initial public offering, according to people familiar with the matter.
Earlier this year, it hired Morgan Stanley, Barclays, Bank of America and Citigroup as bookrunners for a deal that would value the company north of $1 billion, these people said.
Depending on how rapidly the company continues growing, that valuation could be much, much higher.
—By CNBC's Kayla Tausche. Follow her on Twitter @KaylaTausche.
This article has been updated to correctly reflect Christy Wyatt's previous employment.