Chord Cadenza is a free (open source) app that helps you to play and improvise chords whilst a MIDI file or audio source is being played. It does this by updating a rolling display to map the chord notes to a piano keyboard. It can also dynamically assign notes or chords to keys on a MIDI or PC keyboard. Synchronisation is achieved automatically from a MIDI file. An audio file (e.g. MP3) can be synchronized and saved using the program. You can also play along to any audio source (e.g. internet stream or other musicians) and synchronise as you go along. Chords and major/minor keys can be extracted from the MIDI file using a configurable tool that analyzes the MIDI file. Chords, keys, and time signatures can also be created or updated manually - this allows you to play along with an audio source without requiring a MIDI file. The program contains a sequencer-style display that can be used to control the volume, panning, muting, solo'ing and patching of the tracks of the MIDI file. Audio can be rendered with the program's builtin synthesizer (using SoundFonts), or an external synthesizer (using the program's MIDI output).