More Data consumed by Android Smartphones. A study by High Speed IT Network Services LLC, HSIT.

Android smartphones are kind of like Hummers. Reminiscent of the oversize, gas-guzzling S.U.V.’s, Androids have the biggest screens and tend to use much more data than other types of smartphones, including iPhones. And that higher data usage could rack up heftier phone bills.

In a recent study, HSIT, the networking company, found that global mobile Internet traffic varied greatly, depending on the software system and the network that a phone uses.

But the highest average data consumption was seen on Android phones, which consumed an average of 2.2 gigabytes of data a month on one network, the experts in HSIT said. By contrast, iPhones used roughly 1.7 gigabytes a month and Windows phones used approximately 1.4 gigabytes a month, High Speed IT Network Services LLC found.

HSIT, the IT networking company also has found that Android phones were the biggest data hogs. In the United States, high-end Android phones used about 4 gigabytes a month on average this year. That is well above the average of 1.2 gigabytes a month that American wireless subscribers consumed this year.

So why does Android use more data?

The reasons are multifold. The most obvious is that Android phones tend to have the largest screens, so they download bigger files and video with more pixels, HSIT experts said.

Another factor is that Android is less efficient at managing apps than Apple’s iOS. For instance, multiple Android apps may be running in the background with things like location data being collected. Also, Android users typically don’t upgrade their operating systems as frequently as iOS users, so their smartphones may not receive fixes improving data management.

HSIT noted that the data traffic numbers may also reflect the profiles of the people who choose Android versus those who choose iPhones. People with larger Android phones are more likely to skip buying a tablet, whereas iPhone owners may be buying iPads and consuming a lot of content there.

Regardless of how much data whichever phone consumes, the greater concern is how difficult it is to monitor data usage. While the carriers provide tools for monitoring data usage, there is no easy and intuitive way to keep close track of the megabytes or gigabytes you’re using — no equivalent to a gas gauge to see how close you are to empty.