T-Mobile and Orange are the latest mobile operators to launch 3G services into the UK, joining 3 and Vodafone.
Both have introduced Universal Mobile Telecommunications System (UMTS)/GPRS datacards. T-Mobile's datacard offers speeds of 128Kbps, while Orange's runs at the full UMTS speed of 384Kbps.
T-Mobile said the speed of its service will increase progressively to 384Kbps in the coming months.
The launch of the T-Mobile service - featuring Wi-Fi access on the same tariff, with access available at more than 500 locations across the UK - comes after trials with more than 150 business customers, including HP.
The promotional launch of T-Mobile's datacard is set to be focused in major business centres, where the operator's 3G coverage is highest.
Brian McBride, managing director of T-Mobile UK, said: "The switch to 3G is not just a matter of speed; it's equivalent to the move from the typewriter to the PC.
"3G datacards give customers internet access at similar rates to those they experience with high-speed fixed-line internet access."
T-Mobile's multimedia package costs £199, plus a monthly fee of £70. It includes unlimited data access regardless of whether usage is on 3G, 2.5G or Wi-Fi.
Orange's 3G offering, first announced earlier this month, features a number of tariffs from low to high usage, including an unlimited flat-rate option that costs £85 plus £75 per month.
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