Bigger smartphone screen size may be better for more than just practical reasons, according to researchers. Participants in a study on smartphones indicated that emotional reasons might influence their decision to buy smartphones with bigger screens even more than practical ones, said S. Shyam Sundar, Distinguished Professor of Communications and co-director of the Media Effects Research Laboratory, Penn State. "There are basically two different reasons that 'bigger is better' for screen size: utilitarian（功利的） reasons and affective, or emotional, reasons," said Sundar. "There are so many things on smartphones that we can use, but an even more powerful factor of the larger screen is its hedonic（享乐的） aspect -- how attractive and pleasing it is to users."

People may find bigger screens more emotionally satisfying because they are using smartphones for entertainment, as well as for communication purposes.

"The screen size has increased the bandwidth of user interactions on smartphones, making it more than a talking-texting device," said Sundar. "With high definition screens, people now can watch television and movies, as well as multi-task, something that wasn't possible in earlier smartphone versions."

The desire for larger screens that drives purchases of other entertainment devices may be part of the impulse to buy smartphones with larger screens, said Ki Joon Kim, adjunct professor in the department of interaction science, Sungkyunkwan University, Korea, who worked with Sundar on the study.

"Large-screen TVs and monitors are known to have positive effects on user experience," said Kim. "Our study found that the same applies to the mobile context as well."

Smartphone engineers cannot increase the size of the screen continually or the mobile device will become inconvenient to carry.

"We have not reached the point where the screen is too big yet, and I believe there may be some room for expansion of the screen size," said Sundar. "Finding the idea size is something that I'm sure industry engineers and designers are working to find." Kim said that this appeal to both practical and emotional needs of users may indicate that smartphones can handle the merging of various forms of media.

"Smartphones serve both utilitarian and hedonic purposes," Kim said. "They are convergent media." The researchers randomly assigned smartphones with two different screen sizes to 130 university students. One of the phones had a 3.7-inch screen and the other had a 5.3-inch screen size. They then asked the participants to visit a mobile website and find the departure time for a shuttle bus.

Participants were then asked to fill out a questionnaire on their experience using the smartphone. The questions included ones on how they used the device, such as whether or not the smartphone helped them locate the bus schedule, and on how they felt about using the phone, such as whether or not they felt excited about using it.