If you have an iPhone, an android or a Windows Phone (or all three, Why not?) and besides you have a camera (in fact if you have any of them you already have a camera) a moon app is pretty basic.
You can know when the moon is going to be full and if it is going to appears in the day, or if it is going to be a new moon or a black moon to shoot stars clearer or without the blue moonlight.
I prefer to shoot it in the day, it’s easier to see its details without disappear the context.
Qhapaq 