The moon
Moonlight brightens the sky more than anything else on a clear night, so the application shows where the moon was. It needs your observing site.
On the calendar
Every date shows the moon’s phase at the middle of that night, whether or not anything was recorded. The pale part is the lit part, as the moon looks in the sky. A faded moon was below the horizon at the middle of the night. A full moon that stayed down all night brightened nothing.
On the night chart
Turn on (and the same setting for the published chart in Chart Snapshot & Upload). A line shows the moon’s height while it is up, on a scale from 0° to 90° on the right. The bottom of the chart is the horizon, so the line starts at moonrise and ends at moonset.
The note under the chart gives the times and how much of the moon was lit, for example moon rises 05:35 · 6% lit, or says the moon was down all night.
Leaving moonlit readings out
In SQM History, tick Moon down only to leave out every reading taken while the moon was up. Use it when you want figures that describe your site rather than the moon. A clear night under a full moon can read brighter than a cloudy night with no moon. The readings left out are counted separately, so you can see how many there were.
It only asks whether the moon was up. It doesn't try to correct for how much the moon brightened the sky, which depends on its phase, height and direction, and no meter measured.