Research In Motion, long the dominant provider of smartphones to business—and until two years ago, the overall market leader—has been hammered by market missteps, delays in new versions of its BlackBerry phone line, and the ascent of Google's Android and Apple's iPhone. Now, according to a report from the Toronto Globe and Mail, the company has reached a tipping point, with analysts expecting the company to acknowledge a worldwide decline in subscribers to the BlackBerry mail and messaging service in its next earnings report later this week.

"This is the first quarter we are expecting zero subscriber growth," National Bank Financial Senior Research Analyst Kris Thompson told the Globe and Mail. In the next quarter, he said, he believed the subscriber base would go into a "downward spiral," with the expected release of the BlackBerry 10 slowing but not stopping the hemorrhaging of customers.

The BlackBerry mail and messaging services are the main reason many enterprise customers have used RIM's devices, and account for about a third of its revenue, based on its most recently quarterly results from June. The company has kept its service growing overseas, but its subscriber base has been in decline in North America as Android and iOS gain more enterprise-friendly features.

In the quarter ending in June of this year, the company shipped 7.8 million BlackBerry phones, and only 250,000 BlackBerry PlayBook tablets. By comparison, during roughly the same period, Apple shipped 26 million iPhones and 17 million iPads.