Interactive geometry software specially developed for
the iPhone, iPad, and
The first construction is a regular hexagon given its center and one vertex. The second construction is the nine-point circle.
Apollonius by Adolfo Rodriguez is an Interactive Geometry Software (IGS, or Dynamic Geometry Environment, DGE) for the iPhone,
iPad and iPod Touch. It allows you to make geometric constructions (such as those made using a compass and straightedge/ruler) and move their parts smoothly using the device's
Apollonius was inspired by similar software for personal computers, such as Cabri
and The Geometer's Sketchpad.