The study notes that approximately 60 percent of college students admit they may be addicted to their cell phone, and some indicated they get agitated when it is not in sight, said Roberts, lead author of the article “The Invisible Addiction: Cellphone Activities and Addiction among Male and Female College Students.”

The study — based on an online survey of 164 college students — examined 24 cellphone activities and found that time spent on 11 of those activities differed significantly across the sexes. Some functions — among them Pinterest and Instagram — are associated significantly with cellphone addiction. But others that might logically seem to be addictive — Internet use and gaming — were not.

General findings of the study showed that:

• Of the top activities, respondents overall reported spending the most time texting (an average of 94.6 minutes a day), followed by sending emails (48.5 minutes), checking Facebook (38.6 minutes), surfing the Internet (34.4 minutes) and listening to their iPods. (26.9 minutes).

• Men send about the same number of emails but spend less time on each. “That may suggest that they’re sending shorter, more utilitarian messages than their female counterparts,” Roberts said.

• Women spend more time on their cellphones. While that finding runs somewhat contrary to the traditional view that men are more invested in technology, “women may be more inclined to use cellphones for social reasons such as texting or emails to build relationships and have deeper conversations.”

• The men in the study, while more occupied with using their cellphones for utilitarian or entertainment purposes, “are not immune to the allure of social media,” Roberts said. They spent time visiting such social networking sites as Facebook, Instagram and Twitter. Among reasons they used Twitter were to follow sports figures, catch up on the news — “or, as one male student explained it, ‘waste time,'” Roberts said.

Excessive use of cellphones poses a number of possible risks for students, he said.

“Cellphones may wind up being an escape mechanism from their classrooms. For some, cellphones in class may provide a way to cheat,” Roberts said.

Excessive or obsessive cellphone use also can cause conflict inside and outside the classroom: with professors, employers and families. And “some people use a cellphone to dodge an awkward situation. They may pretend to take a call, send a text or check their phones,” Roberts said.

Roberts noted that the current survey is more extensive than previous research in measuring the number and types of cellphone activities. It also is the first to investigate which activities are associated significantly with cellphone addictions and which are not.

Study participants were asked to respond to 11 statements such as “I get agitated when my cellphone is not in sight” and “I find that I am spending more and more time on my cellphone” to measure the intensity of their addiction.

The study noted that modern cellphone use is a paradox in that it can be “both freeing and enslaving at the same time.”

“We need to identify the activities that push cellphone use from being a helpful tool to one that undermines our well-being and that of others,” Roberts said.

Cellphone activities examined in the study included calling, texting, emailing, surfing the Internet, banking, taking photos, playing games, reading books, using a calendar, using a clock and a number of applications, among them the Bible, iPod, coupons, Google Maps, eBay, Amazon, Facebook, Twitter, Pinterest, Instagram, YouTube, iTunes, Pandora and “other” (news, weather, sports, lifestyle-related applications and Snapchat.)