The company also plans to unveil more new business outside the Facebook platform

American social-game developer Zynga is expected to launch several new games in Tuesday in hopes of boosting share prices.

Zynga will hold a conference called "Zynga Unleashed" in San Francisco in Tuesday and has invited media and analysts to attend. Analysts expect the company to display a variety of games to be released this year, and to further clarify the company's business model "FarmVille" and "CityVille" Zynga games still rely heavily on the Facebook platform.

In addition, the company plans to unveil more new businesses outside the Facebook platform, including mobile games and zynga.com platforms. "We will be more optimistic about growth prospects if their portfolio can cover a wide range of sectors, not just across multiple platforms." "Colin Sebastian, analyst at US investment company Robert W Baird, said Colin Sebastian.

Sebastian gave Zynga a rating for the outperform, and said the company would be well on the way to breaking out of the existing areas of casual gaming and into areas between casual games and big games. This, he says, includes more challenging products such as shooting and racing, but simpler than similar games on the game consoles.

Another important aspect is the market performance of Zynga's existing games. All of Zynga's games are available to users free of charge, and the only profitable channel is game shopping. But with Facebook's credit-trading system, part of the revenue is shared with Facebook.

The market's concerns about Zynga have focused mainly on weak user growth. According to AppData, a third-party agency, Zynga's monthly active users grew only 2% per cent last month, and the number of active users even slipped 1%.

This has also led to the pressure on Zynga's shares. Although the unit rose 8% per cent last week and rose slightly in early Monday, to $6.03 trillion, it is still 40% per cent lower than the $10 trillion issued last December. Compared with the top 14.69 dollars in early March, it was a 60% drop.

"The market is not buying it. "Michael Pachter, an analyst with Wedbush Nomura, an American securities firm, said of the Zynga business model. He points out that Zynga games may be popular, but the most popular games are not necessarily the most lucrative.

"They need to attract a large number of users to play the game, in order to find long-term participation in the game's core players." The core player is the real source of revenue. Pacht said he gave Zynga a "outperform" stock rating.