Apple Inc and China Unicom, officially partners since they signed a deal in March 2009, appear to be in a head-to-head battle for sales of the iPhone 4, which was launched Saturday.

China Unicom is selling the handset with a two-year contract, but Apple stores are offering the phone with no-strings-attached. Buyers are free to use the services of any telecom provider.

China Unicom had over 200,000 pre-orders for the iPhone 4 as of Friday, Wen Baoqiu, a spokesperson with China Unicom confirmed Saturday. He said first day sales data is not yet available.

Apple declined to give sales figures.

The iPhone 4 went on sale in four Apple stores in Beijing and Shanghai Saturday. At the same time, the product, bundled with a two-year mobile service contract, is available through China Unicom's retail stores and authorized Suning Appliance outlets across the country. China Unicom launched iPhone 4 pre-orders September 17.

Buyers may choose to shop at Apple stores because of lower out-of-pocket costs, while some may simply not wish to change phone numbers - something they would have to do if they do not have a China Unicom account, said Fu Liang, an independent analyst.

Consumers have so far voiced little interest in being tied to a contract.

In an online survey released Saturday by portal site 163. com, over 70 percent of the more than 7,000 respondents polled said they would choose to buy an iPhone 4 from Apple instead of China Unicom.

"Apple's deal with China Unicom is becoming more like that of a competitor," indepen-dent analyst Fu said.

"Apple does not want to be tied to one single service provider."

Apple Inc is also undercutting China Unicom's price for the new iPhone.

The retail prices of iPhones bought through Apple are around 1,000 yuan ($149.14) less than those sold by China Unicom.

But the news may not be all bad for China Unicom.

Fang Hua, a Website developer in Beijing, said he plans to purchase an iPhone from China Unicom.

"People like me who use mobile services all the time would choose the China Unicom contract because it gives calling and web-surfing discounts," Fang said.

Analysts said that China Unicom might do well to move away from its single-minded focus on the iPhone.

"It is not wise for China Unicom to pay too much attention to a single brand because there are other alternatives available out there in the market," Fu said.

Smartphones that run the Google's Android operating system pose a serious challenge to the iPhone, Fang said.