Scrolly setup takes a few minutes and needs no account migration, no desktop software and no configuration file. There are four steps: unbox the tag, install the app, pair them, pick your apps.
One: take the tag out of the box. There is nothing to charge and nothing to assemble. Two: install the Scrolly app from the App Store or Google Play. Three: pair the app with the tag. Four: choose which apps and websites you want blocked, and set a schedule if you want blocking to start and stop on its own.
After that, tapping your phone against the tag switches blocking on. Tapping again switches it off. That is the entire daily operation.
Blocking apps on a phone requires the operating system's own screen-time permission, so the app will ask for it during setup. Without that permission it cannot block anything, which is true of every blocker on either platform, not just this one.
You need both the tag and the app for everyday blocking. The app on its own will not block anything, and that is deliberate - a blocker you can switch off from inside the same phone is a blocker you will switch off. Losing the tag is a separate case and does not lock you out.
The blocked-app list is not fixed at setup. You can add or remove apps, change schedules, and adjust how long the timed pauses run, at any point.