Travellers to China would be well-advised to check their mobile mapping clients before embarking, after it emerged that customs officers have been given the power to confiscate any device featuring illegal maps, such as those mislabelling important islands.

The new policy would see any mobiles or tablets seized at the border transferred to the National Administration of Surveying, Mapping and Geoinformation (NASMG) for further investigation, according to Xinhua.

An ‘illegal’ map could apparently be one that ascribes Middle Kingdom territories to other nations, features mistakes in the location of the Chinese border or leaks confidential information about sensitive military and other locations.

Taiwanese officials recently complained to Apple after its maps app identified, with gloriously high-resolution imagery, a new state-of-the-art early-warning radar installation located near Hsinchu airbase.

China has always had particularly strict rules governing the mapping of its territory, restricting licenses to only a handful of firms.

It recently announced plans to increase fines for those failing to include territorial outposts and a requirement that all web-based map providers locate their services within China.

These latest moves can probably be viewed as a response to the simmering maritime territorial disputes with other Asian nations which flared in recent months with violent nationwide protests after Japan decided to buy the contested Diaoyu/Senkaku Islands.

It’s not entirely clear whether Google or Apple’s map clients would land an unsuspecting traveller to China in trouble under the new regulations.

A cursory search on Google Maps shows the islands labelled by their Chinese, Japanese and Taiwanese names, while Apple Maps has apparently duplicated them, to give one set each to China and Japan. ®