Thread moved to the Smartphone forum.
UPDATE: I did some additional research, and it sounds like much of what I wrote below is out of date, if you are a Verizon subscriber. This carrier does not have a cap, just a warning that if it thinks you are abusing its wireless network, it has the right to cancel your service.
So it sounds like you could get an unlimited data plan and sign up for the tethering plan, and you're good to go.
Still, if you're the sort of person who's going to download a Blockbuster movie every night you might want to think about an alternate plan.
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Using your smartphone as the only source for home Internet access is quite doable, providing your needs are modest.
All the carriers have a "hard" or "soft" cap on how much wireless data you can exchange, depending on what your service plan is. Basically, this means that you can transfer a few gigabytes of data, but if you get extreme you're going to have problems.
If you're a Verizon customer, the cap is 5 GB. AT&T subscribers max out at 2 GB.
Most customers will be fine if they just want to use their smartphone's mobile hotspot feature to check your email and do some Web surfing, but if you're into streaming video or audio you're going to run into the cap.
If you pay the extra money for a cable model or DSL, there is no cap. The sky's the limit.
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