Tablet computers and smartphones take centre stage at a major Asian telecoms fair that opens Tuesday, with struggling phone maker Nokia making a new push to reverse its eroding fortunes.

Industry behemoth Apple, whose iPad has a stranglehold on the tablet market, will be absent from the CommunicAsia expo, preferring to stage its own iconic events in California.

But Nokia will be back after a 10-year absence as the troubled Finnish giant looks to make a big splash in a bid to regain its market share, which has been eaten up by Apple and other rivals.

It will be joined by Asian brands as well as BlackBerry maker Research in Motion (RIM) of Canada at the four-day trade event.

Nokia's chief executive Stephen Elop will deliver a keynote address Tuesday in which he will provide an overview of the company's new strategy and an update on its partnership with US software giant Microsoft.

Elop is also expected to speak on the importance of the regional market to Nokia, which accounted for at least eight out of every 10 phones sold in Asia in its heyday, according to CommunicAsia.

Nokia declined to say why the company decided to return to the expo after its last participation in 2000 but one analyst said the move showed how important the region is to the company's future.

In the intervening period, Nokia had held solo exhibitions outside the CommunicAsia venue in what was seen in the industry as a sign of supreme confidence in its brand.

But times have changed after Apple and other companies like Samsung eroded the Nokia hegemony.

While it remains the world leader in mobile phone handsets, Nokia has seen its global market share dwindle.

Nomura Equity Research forecast in a report that Nokia's market share in terms of the number of units sold -- for both smartphones and feature phones -- is expected to decline from 25.1 percent in the first quarter of this year to 19.9 percent in the fourth quarter.

In the smartphone sector, the decline is steeper, from 25.5 percent in the first quarter to 13.1 percent in the fourth quarter, according to Nomura.

Until competitive new products are launched, "it is hard to see how management can arrest this decline", the report said.

While pleased with Nokia's return, show organiser Singapore Exhibition Services says this year's fair -- held for the first time at the massive Marina Bay Sands exhibition centre -- will also feature a number of first-timers including social game titan Zynga.

San Francisco-based Zynga is the creator of massive hits such as FarmVille and Cafe World that have drawn millions of followers globally.

A spokesman for RIM said the Canadian handset maker will be displaying its Playbook computer tablet and new BlackBerry Bold 9900 touchscreen smartphone at its booth.

Chinese telecom giant Huawei Technologies, which has been a part of CommunicAsia since 2000 and boasts the biggest exhibit space this year, will showcase its new Huawei MediaPad tablet that runs on Google's Android platform.