Teenagers using smartphones, lonely teenager looking at phone, young people on social media, teenagers scrolling on phones, teen mental health, social isolation among young people, online friendships, digital communication, friends talking face to face, teenagers hanging out together, young adults socializing, group of friends outdoors, teenagers sitting together looking at phones, smartphone addiction, youth loneliness, emotional wellbeing, real life friendships, teenagers spending time offline, young people talking in a park, social media and mental health