TORONTO — Not only did Research In Motion Ltd., the maker of the BlackBerry smart phone, see its profit more than double last quarter, it may have gotten a boost from a top competitor's strong sales.

RIM has benefited from Apple Inc.'s introduction of the iPhone in June because it brought attention to smart phones, and more people are starting to use them, said Canaccord Adams analyst Peter Misek.

"People are starting to realize, 'Why should I buy a Razr when I can buy a BlackBerry or an iPhone?' I think the iPhone was the single biggest blessing RIM ever had," Misek said.

The Waterloo, Ontario-based company earned $412.5 million, or 72 cents per share in its fourth quarter, which ended March 1, up from a profit of $187.4 million, or 33 cents per share, in the same period a year earlier.

Revenue jumped to $1.88 billion from $930 million.

Analysts polled by Thomson Financial, on average, expected a profit of 70 cents per share on sales of $1.86 billion.

U.S.-traded RIM shares rose $5.46, almost 5 percent, to $121.25 in after-hours trading Wednesday after closing at $115.79.

After enjoying years of success in the corporate market, RIM has targeted the consumer market with push e-mail software that allows customers to access their e-mail on their wireless devices in real time.

"It's much more of a mainstream thing," co-CEO Jim Balsillie said on a conference call with analysts.

Balsillie said RIM hasn't seen any signs of a slowdown in its business because of a slowing U.S economy.

It added 2.2 million new subscribers during the quarter, bringing its total to more than 14 million, and it shipped about 4.4 million smart phones.

Apple has said it sold 2.3 million iPhones in the quarter that ended Dec. 29, for a total of about 4 million in the six months since the device's launch.

BlackBerry's smart phones are cheaper than iPhones, and many people consider them easier to use for e-mail and text-messaging because they have traditional keypads instead of touchscreens.

RIM said it expects earnings per share in the first quarter of its fiscal 2009 between 82 cents and 86 cents per share. Analysts were expecting 76 cents.

Duncan Stewart, president of Duncan Stewart Asset Management, said he is astonished that a company the size of RIM has doubled its revenue. He called RIM recession-proof.

"People may be spending less money on cars, they be spending less money on their houses, but it turns out the BlackBerry is the one essential," Stewart said.