• A half-moon glides slowly back and forth across a night sky.
• There is nothing to tap and nothing to follow. Just rest your eyes on it.
• The screen stays awake the whole time, then eases to black in the final wind-down.
• When the timer ends the screen is let go, so the phone can lock itself as normal.

Set how long the drift lasts in Settings, from five minutes up to half an hour, or with no time limit at all. The glide speed drifts on its own, a little faster then a little slower, so it never feels mechanical.