Excessive smartphone use can have various negative effects on adolescents' psychosocial development. One of these negative effects is that adolescents have problems in controlling and expressing their emotions, in other words, in using emotion regulation skills. On the other hand, the presence of emotion regulation skills in adolescents may also serve as a protective factor in preventing smartphone addiction. The aim of this study is to examine the relationship between smartphone addiction and emotion regulation skills in high school students. In addition, in line with the findings, it is aimed to provide strategic recommendations for educators and to develop solutions to encourage students' healthy use of technology.

Mixed research method was used in the study. The participants of the quantitative part of the study consisted of 178 students studying in high school; the participants of the qualitative part consisted of 10 students. Convenient sampling was used to determine the participants from whom the quantitative data of the study would be collected, and purposive sampling methods were used to determine the participants from whom the qualitative data would be collected. When the smartphone usage times of the students were analyzed, it was seen that the maximum usage times of the students were between 3-5 hours a day and 5-7 hours a day. The majority of students use their smartphones to follow their social media accounts. This usage purpose is followed by messaging, talking and playing games.

According to the findings obtained as a result of the analysis of quantitative data, while students' emotion regulation skills do not differ according to their gender, their smartphone addiction shows a significant difference in favor of women. One of the important findings in the analysis of qualitative data is that almost all of the students see themselves as smartphone addicts. They define smartphone addiction as not being able to do without the phone and not being able to leave the phone in their hands whenever they want. They stated that the use of the phone relaxed them emotionally. They stated that when they are sad or angry, they feel relieved when they watch funny videos or watch their favorite TV series. They also emphasized that this feeling of relaxation is temporary. They said that their anxiety increased when they saw people who were in a better financial and/or moral position than them in videos or social media accounts while using their phones. Other strategies used by high school students to cope with their negative emotions were sleeping, cooking and going out with friends to have fun.

Although the findings of the study suggest that there is no relationship between smartphone addiction and emotion regulation skills, using smartphones is one of the strategies that students stated that they use to cope with their negative emotions. The results of the research show that students have high levels of smartphone addiction and low levels of using emotion regulation skills. Educators should guide students to gain emotional awareness and organize activities that develop self-regulation and social-emotional skills. In order to reduce phone addiction, awareness should be created in students, digital detox should be encouraged and they should be directed to artistic, sportive and social activities.

Keywords: Secondary school education, smartphone addiction, emotion regulation skills.