The explosion in the use of smartphones to access the internet can also result in a huge hole being blown in your bank account, as one subscriber found out when presented with a HK$183,000 mobile phone bill.
To combat what is termed 'bill shock', the Office of the Telecommunications Authority yesterday launched a campaign in the run-up to the festive season to make users aware of 'mobile data traps', especially when travelling overseas.
According to the authority, the number of mobile broadband users increased from 3.2 million last year to 4.64 million this year, with the total volume of mobile data usage soaring from 384 terabytes to 1,236 terabytes - 1 terabyte is a trillion bytes, or 1,000 gigabytes.
'Using smartphones to browse the internet, access e-mails and updating Twitter while travelling abroad is enjoyable, but it could result in astronomical fees for mobile data roaming services,' warned Danny Lau Kwong-cheung, an assistant director of the authority.
He said the authority received 1,083 complaints about mobile data services between January and November this year, compared with 337 in all of last year, and most involved billing disputes.
Consumer Council figures also show the problem has been worsening, with complaints jumping from 473 last year to 1,491 in the first 11 months of this year.
The total amount of money involved in these complaints also rose to HK$3.1 million, from about HK$1 million, with one case featuring a bill of HK$183,000.
'Most bill shock cases are due to the accidental or unintentional use of mobile data services,' Lau said.
He added that the authority had handled one complaint where a user was charged HK$80,000 for using mobile data while travelling overseas.
However, he said the situation in Hong Kong was not too bad, unlike the United States where almost one in every six mobile users experienced 'bill shock'.
'We have introduced guidelines for mobile operators to help prevent this, such as allowing customers to opt out of the service, setting a usage cap, or alerting the customers about unusually high usage,' Lau said.
The authority had also launched a publicity campaign this month to educate the public on how to be a smart user of mobile data services, he said.
The campaign included television commercials, public forums and a website.
Despite the authority's guidelines, options offered by mobile operators can vary greatly.
For example, China Mobile Hong Kong users can choose a mobile data service that becomes suspended if unusually high usage is detected.
CSL only allows this option to those under 12 or over 60, although it offers a prepaid day pass service to limit usage.
PCCW does not offer a usage cap, but plans to cap charges are available.
Referring to calls for laws to limit the charges, non-affiliated legislator Samson Tam Wai-ho, who represents the information technology sector, said: 'It is best to let market forces operate.'
More tips on the use of mobile data services are available at http://www.mobilenet.gov.hk/en/home/index.html 
The total amount of money involved in mobile data complaints rose to, in HK dollars: $3.1m