250,000 days of adult phone data: usage barely predicts mood
What they found
Adults' phone use barely predicted their mood, that week or the next. Age and gender predicted it better: younger adults, women and genderqueer or transgender participants reported lower mood.
How they know
10,099 US Android users shared four weeks of logged minutes in social and other apps and got one mood question each morning. Links were tiny or absent in both orders - use before mood, and mood before use.
What it means for you
Screen time alone says little about how you will feel next week. The authors point to what happens on screen, which went unmeasured.
The limits
Four weeks cannot show slow effects. Self-selected adults, mostly white, female and college-educated; no teenagers. One self-rated mood question daily. Correlational: cutting back went untested. Five authors worked at Google, one consulted for Snap; university staff ran the statistics.
This is a short takeaway in our own words, not a reproduction of the study. For the method, the sample and the caveats, read the original.
