Pete Cunningham, an analyst at Canalys, a research firm in Reading, England, said iOS would be more prevalent than Windows in 2016, holding 18 percent of the market compared with 15 percent for Windows. Mr. Cunningham sees Windows Phone 8 helping Nokia solidify its comeback, but not catapulting the company to the position of market leader.

“I don’t think we are going to ever see Nokia return to the dizzy heights it was once at,” Mr. Cunningham said Friday. “Can Nokia build a sustainable business in this space? We think it can. Windows 8 will help them do that. But the market dynamics and power have shifted.”

The Chinese cellphone makers Huawei and ZTE could use their domestic success to expand globally, challenging Nokia’s fragile foothold, Mr. Cunningham said. Some might expand their own lines of Windows phones to avoid the fate of Samsung, which was fined $1 billion last month by a U.S. District Court jury for infringing on Apple’s patents with its Android devices.

Samsung, the global market leader in cellphone sales, could also decide to shift its smartphone emphasis from Android to Windows. Mr. Jeronimo, the I.D.C. analyst, said he expected Samsung to do exactly that in 2016, after Nokia and Microsoft have made the necessary investment to build Windows into a credible third operating system.

Samsung introduced the first Windows Phone 8 handset, the Ativ S, on Friday.

“They will do what they did with Android,” Mr. Jeronimo said. “They will swoop in and take over the market in Microsoft phones.”