Smartphones, which enable us to be online everywhere and every time, are also commonly used by students today. This study aims to reveal undergraduate students' habits of using smartphones. With this purpose, the phone usage track application was installed on students' smartphones, and their 7-day use was recorded with the application and was then analyzed. In addition to that, the students' views on using smartphones during classes were also investigated through open-ended questions. As a result, it was found that they used their smartphones for 4 hours and 50 minutes on average and that they used the same or different applications approximately 380 times a day. The most frequently used smartphone applications were found to be social media and messaging applications. The students were found to use their smartphones the most intensely between 21.00 and 24.00. The majority of the students used their smartphones during classes and their reasons for using the phones for noneducational purposes were more than the reasons for using them for educational purposes. The students stated that they used their smartphones for non-educational purposes such as check the time, make calls, and texting and for educational purposes such as research, take the photo of the blackboard or slides. While the great majority of the students had negative views about using smartphones during classes, some of them also had positive views.