Apple has appeared in a Shanghai court after a Chinese firm accused the tech giant of copying its software for the Siri personal assistant service found on iOS devices.

Shanghai's Zhizhen Network Technology Co claims Apple infringed its patent for voice recognition software, and the two companies will exchange evidence at a pre-trial hearing, representatives of the Chinese firm said on Wednesday.

"The company will ask Apple to stop manufacturing and selling products using its patent rights, once Apple's infringement is confirmed," Si Weijiang, a lawyer representing Zhizhen, told the AFP news agency.

"We don't exclude the possibility of demanding compensation in the future," he added.

The legal challenge comes after Apple last year paid $60m to Chinese computer maker Shenzhen Proview Technology to settle a long-running battle over the "iPad" trademark, whose ownership was claimed by both companies.

Apple has also come under fire from state media in recent days over its customer service and return policies.

Zhizhen says it patented its "Xiao i Robot" software in 2004, while Apple's Siri, which made its debut with the release of the iPhone 4S in 2011, was first developed in 2007.

Siri, described by Apple as an "intelligent personal assistant", responds to a user's commands through voice recognition software.

The Chinese company's product operates in a similar way and works on Apple's iOS operating system as well as rival Android.

It has wide application in areas including telecommunications, finance and e-commerce and Zhizhen claims more than 100 million users in China, according  to a statement.

An official of the Shanghai Number One Intermediate People's Court confirmed the hearing had started, but declined further comment.

Apple did not respond to request for comment.

The full case is scheduled to be heard in July, Zhizhen spokeswoman Mei Li told AFP.

"We surely have confidence, our lawyers also told us they have confidence, but of course we will have to see how the judge will rule," she said.

Source: Agencies