Exactly. If more people's reaction, instead of searching an app store for a privacy respecting screen light, was to sit down and write:

    <!DOCTYPE html>
    <script>let on  true;</script>
    <body onclick="on = !on; this.style.background = on ? 'white' : 'black'">

and were able to easily upload it somewhere on a phone and run it locally from a shortcut on the screen. We'd have hacker culture encouraged right there.