The world's two largest cellphone makers, Nokia and Samsung Electronics, have unveiled their latest rivals to the iPhone as Apple became the top profit generator in the handset industry.

Apple Inc overtook Nokia in the September quarter as the cellphone maker generating the highest total operating profit in the industry, research firm Strategy Analytics said.

Nokia said on Tuesday it had started deliveries of its top- of-the-range N900, while Samsung Electronics Co Ltd announced it would launch its own open mobile platform, bada, in December as it tries to make up for a late start in the smartphone market.

Nokia and Samsung together sell around 60% of all cellphones globally, but they have lost some ground to Apple and Research In Motion Ltd, maker of the Blackberry.

The N900 model is the first Nokia phone to run on the Linux Maemo operating system, which analysts see as key for Nokia to regain ground in the coming years.

While Nokia has lost ground in the smartphone business, it is still the world's largest smartphone maker by volume. Samsung's volumes are well behind Apple, RIM and HTC Corp.

But measured by profits, Nokia lost in the third quarter against Apple, which entered the cellphone market only in mid-2007.

Apple does not unveil profits per business line, but Strategy Analytics estimated Apple's operating profit for its iPhone handset unit stood at $1.6 billion in the third quarter, compared with Nokia's $1.1 billion.

"With strong volumes, high wholesale prices and tight cost controls, the PC vendor has successfully broken into the mobile phone market in just two years," said Alex Spektor, an analyst at Strategy Analytics.

Apple sold 7.4 million iPhones during the July-September quarter, generating sales of $4.5 billion. Nokia sold 108.5 million phones in total in the same quarter, generating sales of €6.9 billion ($10.36 billion), but its profits were hurt by the economic downturn.