This study investigated how technology use impacts academic performance. A proposed model postulated that academic performance could be predicted by a cognitive independent variable-executive functioning problems-and an affective independent variable-technological anxiety or FOMO (fear of missing out)-mediated by how students choose to use technology. An unobtrusive smartphone application called "Instant Quantified Self" monitored daily smartphone un-locks and daily minutes of use. Other mediators included self-reported smartphone use, self-observed studying attention, self-reported multitasking preference, and a classroom digital metacognition tool that assessed the student's ability to understand the ramifications of technology use in the classroom that is not relevant to the learning process. Two hundred sixteen participants collected an average of 56 days of "Instant" application data, demonstrating that their smartphone was unlocked more than 60 times a day for three to four minutes each time for a total of 220 daily minutes of use. Results indicated that executive functioning problems predicted academic course performance mediated by studying attention and a single classroom digital metacognition subscale concerning availability of strategies of when to use mobile phones during lectures. FOMO predicted performance directly as well as mediated by a second classroom digital metacognition concerning attitudes toward mobile phone use during lectures. Implications for college students and professors include increasing metacognition about technology use in the classroom and taking "tech breaks" to reduce technology anxiety.