Verizon also has an overage charge of $15 per 1GB of data for exceeding a plan's allowance. Theoretically, if a customer purchased 10GB for $100, then used an added 10 GB without arranging for it in advance, the overage would be $150, for a total monthly data charge of $250.
While Raney, Sherman and others questioned whether many users would need 20GB in a month, that amount is relatively easy to hit if shared across 10 users.
As an example, a single cellular download of a high definition full-length movie can use up more than 3GB of data -- downloading the movie for 7 users would exceed the 20GB limit.
AT&T evidently saw the probability of 10 users wanting 20 GB by including it as the top tier in its published Mobile Share plan, coming Aug. 23.
Both the Verizon and AT&T plans fix a monthly cost per device in addition to the shared data cost.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen, or subscribe to Matt's RSS feed . His e-mail address is email@example.com.
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