The National reviews the app f.lux, which is designed to reduce the blue light from technology that can disrupt sleep.
The friend sent me back a link to f.lux, an app that automatically detects where you are and what time it is, and adjusts the light emitted by your screen accordingly. You can tell the app when you wake up and go to bed, and it will give your laptop or phone a sweetly rose-tinted look at sunset, and an even deeper orange colour at bedtime.
It may feel strange watching Seinfeld with a tangerine filter, but for the period of time I have been trialling it, it seems to be working. I haven’t been falling into the usual trap of feeling exhausted at 10pm but perking up at 11pm after an hour of TV, and it feels gentler on my eyes when I am working late and staring at a screen for less relaxing reasons late at night.