Hide Your Phone When You’re Trying to Work. Seriously.
The biggest roadblock to your productivity is the smartphone on your desk. The Journal of the Association of Consumer Research found that the mere presence of your phone, even if it’s powered off, and even if you’re actively and successfully ignoring it “reduces available cognitive capacity,” which the study’s authors call “brain drain.”
https://www.nytimes.com/2018/12/02/smarter-living/be-more-productive-hide-your-phone.html