Learning to distinguish between the states of matter and being able to provide explanations in terms of molecular kinetic theory is part of basic science education. ODYSSEY States of Matter includes manipulable dynamic models that allow for exploring the differences between the physical states of a number of substances of varying complexity.

For easier visibility, an initial set of models makes use of a two-dimensional (rather than three-dimensional) description. Based on analyzing the structure and dynamics of a system of disk-like particles, universal differences between the three states of matter are discussed. Phase transitions can be observed when the system density is changed. The possibility of encountering solids in an amorphous rather than crystalline state is considered. Realistic three-dimensional models for the physical states of seven common substance (acetone, ammonia, argon, bromine, carbon dioxide, methanol, and water) are available for further exploration.

Using simple gestures, models can be examined at any orientation and zoom level and with a number of different visualization styles. The motion of atoms and molecules can be traced, and the local surroundings of arbitrarily selected particles can be highlighted. A glossary, comments section, and a set of multiple choice questions complete the app.