Before I read "custom phone app", I was imagining a mysterious physical red button somewhere up a telephone pole you had to climb, which through some abuse-of-job-privileges-or-connections you had wired directly into the telephony wires leading into your house. Or perhaps a comically large high-voltage pull switch labelled "reddit" which sparks a bit for no reason. Maybe a series of such pull switches, one for every major distracting website.

I wish you hadn't clarified.