London, UK (AHN) - Sales of mobile data cards has been predicted to increase and reach $3 billion in the next three years posing tough competition to the WiFi hotspot market.

Infonetics Research also forecast that the number of subscribers of the cards used for downloading music, games and video clips to mobile devices, including laptops, will reach 144 million by 2011.

Infonetics said the roll out of more 3.5G or high speed down link packet access (HSDPA) mobile phones increase, launching of more generous download limits on data plans and offering of cheaper mobile data cards will drive the increased sales.

Worldwide sales of smart phones reached $36.7 billion in 2007 with Nokia as the leading brand. There are currently 185 commercial HSDPA networks in 80 countries. The total number of mobile subscribers worldwide is more than three billion.