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.
Just coming here down to note that despite, or because the lizard part, our brains are wonderful creation machines. All the comments up to this parent, including the mysterious physical red button, are great.
On my part, I think the trick is being selective with the addictions we indulge in. Exercise, reading, having sex, cooking, going on walks, writing, 3D modelling. A good mix of addictions is great in life!
I wish you hadn't clarified.