When viewing the moon through binoculars, the moon is 'the right way up'; i.e. it's orientation is the same in binoculars as it appears in the sky. When looking through an astronomical telescope, however, the moon is inverted (upside down). Four icons on the toolbar represent the view that LunarPhase Pro is displaying:

This represents the 'normal' view

Represents the view through an astronomical telescope
(upside-down and flipped left to right)

Star Diagonal:
Represents the view through a telescope that uses a diagonal

Telescope With Star Diagonal:
Represents the view as seen through a telescope that flips the view
left to right only.