A Chinese firm has developed a special protective case known as the "Apple Peel" for converting the iPod Touch media player into a mobile phone, state media said Tuesday.

The Apple Peel 520 from Shenzhen-based Yosion Technology is expected to be available next week in online stores and is targeted at aspirant owners of Apple's trendy iPhone who are baulking at paying the full price.

The device attaches to the iPod Touch like a protective case but has a dock connector, an extended battery and a SIM card slot, enabling users to make phone calls and send text messages, the Beijing News said.

Users who unlock their iPod Touch can install the rubber and plastic case for 388 yuan (57 dollars).

The iPhone became legally available via China Unicom, the country's second-largest mobile operator, in October -- more than two years after its US debut.

An iPod Touch costs around 1,500 yuan in China, compared with 4,999 yuan for the Apple smartphone.

Sales of iPhones in China were initially sluggish as the price was much higher than for those sold on the grey market, which has been thriving for years.