Most Hong Kong mobile numbers start with 9, though numbers starting with 5 and 6 were added in 2000. Photo: May Tse
Hong Kong mobile numbers may have to start with 'unlucky' 4 and 7 as vacant numbers get used up
Inauspicious digits could be pressed into service as city's dwindling supply of numbers is used up
Most Hong Kong mobile numbers start with 9, though numbers starting with 5 and 6 were added in 2000. Photo: May Tse