T-Mobile introduced a temporary promotion offering two lines of service with 6 GB of monthly LTE data each and unlimited talk and text for $80 a month.

The campaign complements a promotion T-Mobile launched earlier this week that offers four lines of talk, text and 10 GB of high-speed data for $35 per line. That campaign was launched alongside an offer of as much as $200 off a tablet for users who buy a flagship Apple, Samsung or LG smartphone on the carrier's equipment installment plan.

As T-Mobile was quick to point out, the latest offer contrasts with a Verizon plan that offers 2 GB of shared data between two lines for $100 a month. And while Verizon charges overages to users who exceed their monthly allotments, T-Mobile opts to throttles speeds when users blow past their monthly caps. Which is why Netflix degrades its video content for Verizon and AT&T but doesn't for T-Mobile and Sprint.

Meanwhile, AT&T quietly increased its fee for users who upgrade their phones from $15 to $20, following Verizon's lead. As MacRumors reported, the nation's largest carrier this week began charging customers who buy devices at full retail price or through a financing plan, claiming the fee will "help cover our increasing support costs associated with customers switching their devices."

AT&T began charging a $15 activation in August before increasing it this week. The fee reportedly applies to users who buy an unlocked phone from a supplier other than AT&T and activate it on their accounts. Sprint's activation fee ranges as high as $30 per device; T-Mobile doesn't charge an activation fee but instead requires a $20 "SIM starter kit" for new phone purchases.

For more:

- see this T-Mobile web page

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