A long time ago I made a program for my laptop which counts down from 90 minutes and shuts down my computer after. Fool as I am, I included a feature which resets the timer, so while in theory it should discourage me from spending too much time on my laptop, in practice I often spent 2 to 4 hours on it, resetting the timer whenever it's about to shut down. I could remove the reset feature, but then I know I would close the program before it shuts down instead.
My issue is, I'm struggling to limit the amount of time I spend on screens, and my own disincentive hasn't worked. Especially a problem after I downloaded Minecraft for my phone. How can I force myself to have regular and decent screen breaks? My mum sometimes comments when I've been on a while and need a break, but I sometimes ignore her too :(.