Create a desktop python app that, can provide the advanced functionalities that are not generally available in the default calendar module.

When run, the application should be able to ascertain the current day, date, month and year using the existing modules (Ex. Calendar) but the rest of the functionalities should be purely computed based on the algorithm and the flow of thoughts captured in the problem statement.

The application expects the learners to compute a future calendar (future month, for that date) or a past calendar (past month) of the given date (today). The application building expects the users to use their knowledge of Python using features such as Python Shell, Python list and sets, dictionary, formatting, utilities, calendar (for verification), geocoder (for lat and long), os and sys and usual program control flow structures.