The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
Apollonius is an interactive geometry app. It allows you to create geometric constructions, such as those that can be made using a ruler and a compass, and subsequently move parts of your constructions to explore the relationship between the geometric objects on the screen. Its interface is especially designed for touch screen, providing one of the smoothest experiences of a any existing interactive geometry app.