π-Base Topology is a community database of topological counterexamples.

The database has:
- Topological Spaces
- Topological Theorems.
- Topological Properties.
- References (Books, Articles, Forums).

Information inside the app:
- Space, Theorem and Property descriptions.
- Properties that are (and aren´t) satisfied by a given space.
- Converses of theorems for which a given space is a counterexample.
- Given a property, which spaces satisfy and don´t satisfy it.
- Counterexamples for the converse of a given theorem. If the converse is True, a proof or reference is given.
- Spaces that satisfy a given logical formula formed with properties (search by formula).
- References.