From https://doi.org/10.1016/j.jesp.2023.104506

Smartphones can undermine the well-being people derive from social interactions, and yet nearly 90% of smartphone owners report having used their phones in their most recent social interaction.

Why do people so readily turn to their devices, if doing so makes them less happy? To investigate this question, we asked participants to spend 20 min with 2–3 unacquainted peers in a makeshift recreation room. We randomly assigned groups to either have their phones accessible or to leave them stored away, and we assessed enjoyment for each 5-min phase of the 20-min period. We predicted that phones would provide some initial benefits; but, over time they would increasingly undermine the enjoyment people would derive otherwise by connecting with others.

Contrary to our hypothesis, phones failed to confer any detectable benefits. Instead, participants who had access to their phones reported worse overall subjective experience and socialized significantly less (on both self-report and objective measures) compared to those who did not have access to their phones. The findings from this registered report cast doubt on the possibility that people are making sensible—albeit myopic—choices to use their phones, suggesting that people may be acting against their own best interest when they use phones in social situations.