A new child's cellphone that doubles as a tracking system w' />

It's the ultimate apron string for parents determined to keep a close eye on the kids.

A new child's cellphone that doubles as a tracking system will soon be released in New Zealand.

The i-Kids phone uses global positioning system technology and sends text alerts when a child leaves nominated safe zones.

Parents can also check their child's location at any time, within a margin of about 5m.

The phone has just been launched in Australia and the company behind its distribution said it was on its way here. Sherri Gullickson, marketing manager for mobiles2go, said she was in final negotiations and expected a firm date within the next month.

"The response [in Australia] has been overwhelming," said Mrs Gullickson. "We think this could be the next big thing in mobile communications."

The i-Kids phone will cost about $300, plus about $30 a month. It is aimed at the pre-teen market, and at parents anxious about child safety.

As well as text alerts when a child leaves pre-programmed safe zones, the phone keeps a record of movements for 30 days. A child is limited to calling four pre-set numbers to help prevent huge phone bills. An emergency button dials each of the four numbers in turn until one is answered. And although the phone can receive texts it cannot send them.

A Vodafone spokeswoman said the technology was available and the company was exploring the options.

Dr Bernard Guillemin, a University of Auckland expert in electrical and computer engineering, said the development of GPS phones was inevitable and likely to mark a boom in over-the-counter tracking devices.

"The ability to locate one's position on the globe to an extraordinary degree of accuracy means there's no doubt we will see more of this."

However, Dr Guillemin said that the technology was not foolproof.

"There are areas that it won't work - in built-up areas or in basements, where a signal cannot get through - so to sell the message that it's revolutionary ... well it has its problems."

Liz Butterfield, director of the internet and mobile phone safety group Netsafe, welcomed "a new dimension in technological capability" but said she was wary about possible misuse.

Devices could be overridden by children, or could easily cross over into surveillance.