Abstract—Augmented Reality has brought significant
contributions to the field of Education. This technology
transformed learning in a more motivating, enjoyable, fun and
interesting activity. This paper presents an Augmented Reality
application for mobile devices that complements and supports
learning of geometric figures. The application, called AGeRA,
consists of a geometry book and software capable of reading
special markers inserted into the book's content. When this book
is placed in front of the camera of a mobile device, 3D objects,
sounds, animations and other interactive elements, leap from its
pages making learning more fun and exciting. Preliminary tests
were made with teachers and students and showed good
acceptance of the application to support geometry teaching.