But even when we're not using them, our devices are still a distraction, according to new research.
Researchers from Southern Maine University found that the mere presence of a person's phone can be enough to divert his attention away from more important, complex tasks.
The researchers asked volunteers from two university statistics classes to participate in two attention exercises, one simple and one more challenging. In one of the classes, they asked students to keep their phones on their desks while they worked on the cancellation tasks. They were told that one of the tasks would ask about the type of phone they used. In the other class, the phones were kept out of vision.
On the simple tasks, both the phone-visible and the phone-away classes performed comparably. But when it came to the complicated tasks, the group without phones on their desks performed significantly better, getting an average of 26 answers correct, while the phone-visible group got 21 correct.
"When the task requires more attention and more executive functioning, then a slight distraction starts to cause a deficit," one of the study's authors, Bill Thornton, told the Huffington Post.
The researchers hypothesize that the phone likely becomes distraction because of our associations with what it provides us -- communication, connection, and access to our social networks.
"Even when you're not using it, it's a reminder of what's out there," said Thornton. "And you're not out there and you're not on it, so it becomes distracting in that sense."
As Thornton and colleagues note, the findings are consistent with prior research which has found that the presence of mobile devices can have a negative impact on interpersonal relationships, even if the phones are not being used.
But is out of sight really out of mind? When it comes to smartphone-induced distraction, it seems that we just can't win. Some research has suggested that among heavy smartphone users, being separated from the device causes anxiety -- likely also increasing levels of distraction.