TORONTO — Energy services giant Halliburton Co.'s move to replace BlackBerry smartphones with Apple's iPhones continues a trend that has been eating away at Research In Motion's traditionally dominant position in the workplace, analysts said Tuesday.

In another shot to the troubled Canadian smartphone maker, U.S.-based Halliburton said Tuesday that it will phase out 4,500 BlackBerrys from its operations and replace them with iPhones over two years.

"It's not, `Oh, oh Halliburton went and everybody is going to go this way,"' said technology analyst Alkesh Shah of Evercore Partners.

"But it's indicative of a long-term trend that RIM is fighting against," Shah said form New York.

For example, some companies are allowing employees to use smartphones like the iPhone as a trend known as "bring your own device" takes root in the workplace, Shah said.

Halliburton said it was making the change after deciding that Apple's technology works better with the programs it uses in the field.

"We are making this transition in order to better support our mobile applications initiatives," said spokeswoman Tara Mullee Agard.

Halliburton, based in Houston, Texas, and Dubai, is one of the world's largest energy drillers and has operations in more than 70 countries.

Shah said Halliburton began to allow its 70,000 employees to use other devices a few years ago and is phasing out the remaining BlackBerrys in the organization.

But employees who need emails instantly delivered and want a high level of security would be the last clients to leave RIM, he said.

"That core user base is probably never going to leave RIM or they're going to have attrition that happens very slowly."

While the loss of any market share can be concerning to investors, the shift of corporate clients away from RIM is more troublesome because they are widely considered a reliable source of income.

Research In Motion (TSX:RIM) has made its reputation and much of its earnings on corporate and government clients that value RIM's direct email delivery and strong encryption.

Caldwell Securities Ltd. doesn't have a policy requiring its employees to either have a BlackBerry or an iPhone.

"But if the firm is paying for one, it's a BlackBerry," said Tom Caldwell, chairman and CEO of Toronto-based Caldwell Securities.

"You can use any system you want to, but typically the partners use BlackBerrys. You still have better security," Caldwell said.

Toronto law firm Osler, Hoskin & Harcourt LLP allows iPhone operating systems 4 and 5 for the iPhone and iPad along with some third-party products.

"We do not have a full 'bring your-own-device' policy in place," said chief information officer Peter Bier.

"Instead, we have security guidelines for devices and if a user device meets these guidelines, then it can be used to connect to our corporate data," Bier said.

RIM has made a strong push in the consumer market in recent years but has been struggling against Apple and other smartphones phones that use Google's Android operating system. Challenges to RIM in the corporate market come as employees bring their consumer smartphone tastes into the workplace.

Technology analyst Troy Crandall said corporations are moving beyond BlackBerrys but not necessarily completely away from RIM.

"We have seen more and more companies saying that they're allowing other devices into the enterprise, even for testing," said Crandall of investment firm MacDougall, MacDougall & MacTier.

And he said pharmaceutical and health-care professions are geared to the iPhone.

"Most of the medical apps are developed for the iPhone. Talk to any doctor, they don't have a BlackBerry. It's generally an iPhone because that's what most of the medical apps are developed for."

RIM has been under close scrutiny for the past year as its shares have eroded more than 75 per cent, with its most recent plunge coming after co-CEOs Jim Balsillie and Mike Lazaridis stepped down from their leadership positions.

The shakeup followed a bad year that included 2,000 layoffs as well operational problems and public relations gaffes.

The Waterloo, Ont.,-based company's stock closed up 12 cents at $16.65 Tuesday on the Toronto Stock Exchange.