Only those that have purchased a phone between November 26th, 2010 and January 10th, 2011 will be eligible, though, and you won't exactly get that cash right away -- you'll first have to first buy and activate your iPhone 4 at the full retail price, send in your trade-in phone within 30 days of activation, and then wait four to six weeks to receive the debit card.

ENGADGET: Verizon ramps up trade-in, upgrade programs in advance of iPhone 4 launch

King bought top-ups for the phone at local supermarkets then sent him the activation codes via text.

BBC: York & North Yorkshire

Compared to regular mobile phone, smartphones generate more revenue in the form of activation fees, service plans and accessory sales.

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Simply insert the SIM from your current phone into iPhone 3G and connect to iTunes 8 to complete activation.

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"While the ability to scroll by tilting a phone is a feature we've seen on some earlier Android models, its automated activation is new, " wrote Gikas of Consumer Reports.

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