According to The Nielsen Company, the average per-user data consumption by U.S. smartphone customers was 606.1MB -- or about 0.59GB -- per month in the third quarter of 2011 (the most recent period for which measurements were available). That's an increase of 39% from the per-user monthly average in the first quarter of 2011 -- and a whopping 80% jump from the per-user monthly average in the third quarter of 2010, just one year earlier.
"For the average person who works and has a social life, 2GB to 3GB is plenty," says Roger Entner, a former Nielsen analyst and founder of telecom research group Recon Analytics. "It takes a very heavy user who is enthralled with their device to really blow through that bucket."
What this says is that, based on current trends, the majority of us can easily stay within the carriers' 2GB-to-3GB-a-month plans -- but most of us would have a tough time keeping within the lower-end, 200MB-to-300MB limits.
Data usage in the real world
All this talk of megabytes and gigabytes is one thing, but let's break down what it really means in real-world terms -- and what it would truly take to exceed that 2GB or 3GB limit.
First, I tracked my total data usage over a full day in which I engaged in relatively heavy Web browsing and social network activity, along with regular email usage and RSS-based feed reading. All of that combined -- and also factoring in any incidental data consumption throughout the day, such as app updates (there was one) and the few kilobytes used here and there by the operating system and random applications -- resulted in a grand total of 30MB of data transferred for the day. That kind of usage would add up to a month-long total of just 900MB -- not even a full gigabyte -- if it stayed consistent over the course of 30 days.
Of course, we use our smartphones for more than just basic browsing. So I also measured the amount of data used in an hour of high-quality music streaming via Pandora. That burned up about 32MB of mobile data -- meaning that, if you streamed a full hour of high-quality music and engaged in heavy Web and social network usage every single day, you'd still be under 2GB for the month.
The activity that consumed the most data in my tests, not surprisingly, was video streaming. Viewing 10 YouTube videos -- a random mix of clips averaging about 3.5 minutes in length, half of them HD and half standard quality -- sucked down a full 125MB of data. So, yeah, if you did that every day, you'd be looking at around 3.7GB of usage for the month.
Bear in mind, though: Most of us don't stream 10 full YouTube videos every single day, so that's an extreme, not something that would regularly apply to most people. (And even if you are watching a lot of videos, you're probably doing a lot of it over Wi-Fi, which doesn't count toward your monthly data limits.) In most typical usage scenarios, you browse the Web heavily on some days and lightly on others. You stream a few videos one day and none the next.
In short, as Nielsen's research reflects, a normal balanced pattern of usage means that your cumulative total can easily stay within the 2GB-to-3GB range -- with plenty of room to spare.
That doesn't necessarily mean you're saving money with a tiered plan compared to one of the old unlimited deals. In practical terms, for most users, things are probably about the same: You used to pay $30 a month for unlimited data; you now pay $30 a month for a 2GB-to-3GB allotment that you rarely (if ever) exceed. Unless you're using so little data that you can get away with one of the 200MB-to-300MB options, the only real difference from the unlimited past to the limited present is that you now have the potential to pay more, if you happen to have a particularly heavy month.