Cell phones are changing habits of Americans in ways you might not have thought much about.

Some 41 percent of cell phone owners fill free time, such as when traveling or waiting for someone, by making phone calls, according to a new national survey of 1,500 people by the Pew Research Center’s Pew Internet & American Life Project, the Associated Press and AOL.

And 44 percent wait to make most of their cell during off-peak hours when the minutes are free.

A full 28 percent of cell phone users say they sometimes don't drive as safely as they should while they their phones. That would seem to support studies that cell phone use while driving is dangerous.

Parents often give cell phone to their teens so they can stay in touch. Yet nearly a quarter of cell owners say they are not always truthful about exactly where they are, and 39 percent of cell users ages 18-29 lie about that.

And cell phones bug us. Consider:

24 percent often feel like they have to answer a call even when it interrupts a meeting or a meal.

22 percent say “too many” people try to get in touch with them because others know they have a cell phone.

82 percent of all Americans (and, oddly, 86 percent of cell users) say loud and annoying cell phone users irritate them at least occasionally.

More than a third of users report being shocked from time to time by their monthly bill.