Shares of Research In Motion Ltd. climbed to a seven-month high Tuesday after the BlackBerry maker said a survey showed application developers’ willingness to endorse its new BlackBerry 10 platform has more than doubled since May.

Fifty-eight percent of developers questioned between May and October said they would recommend BlackBerry 10, according to a report by Pivot Point Research commissioned by Waterloo, Ontario-based RIM.

The shares climbed 6.1 percent to $12.60 at the close in New York, the highest price since May 2. The stock has doubled since Sept. 24, just before the company’s last earnings report, though it remains down 13 percent this year. RIM is scheduled to report earnings Dec. 20.

After years of losing ground to Apple Inc.’s iOS, which powers its iPhones, and Google Inc.’s Android, RIM is counting on the BlackBerry 10 smartphones to resurrect its fortunes. The breadth and depth of the application’s ecosystem is an increasingly critical factor in its success and RIM has been criticized in the past for not making its platforms easier to develop.

Alec Saunders, RIM’s vice-president, developer relations, who has been traveling the globe in recent months talking up how BlackBerry 10 is an improvement on what came before, said this is a sign of progress.

“The focus we have had on building a true developer ecosystem and community is clearly working,” he said in a statement Tuesday.

Still, the challenge he faces was underscored by a report last month which showed RIM’s share of U.S. smartphone sales in the 12 weeks ended Oct. 28, tumbled 6.9 percentage points to 1.6 percent from a year earlier. RIM’s new BlackBerry 10 phones will be unveiled Jan. 30 before going on sale on “multiple continents” in February.