This is the MoonMonth Date Details Pop-Up.

It shows the date details in a larger font, as well as the names of the solar month.

The sample here, however, shows the same view for all the days. Tapping Cancel returns to the Month View.

MoonMonth shows only the current month, the FullMoon application, provides a full Hijri Monthly Calendar, with a library of important days and events, which you can search, edit and to which you can add events of your own. It also notifies you about the next important event of your interest.