It’s not grownups’ imagination: Teenagers really are checking their phones over 100 times a day. According to a new study from Common Sense Media and the University of Michigan Ann Arbor’s C.S. Mott Children’s Hospital, teens aged 13 to 18 regularly receive hundreds of notifications a day from apps like Snapchat, Discord and Instagram. Even though teen usage of Snapchat is rapidly plummeting, the study found, those hours are being steadily replaced—and ramped up—by time spent on TikTok. The video-based social app is particularly addictive, offering “bite-size pleasure and low-friction interaction that quickly adapts to the user’s interests or mood.” Fast Company calls it “quick hit” syndrome—with one video quickly turning into ten. Before teens know it, they’re spending upwards of seven hours a day on the app. Overall, the study results are both illuminating and damning, offering empirical evidence that apps are designed to attract teens to their phones and keep them there for hours