Song Compose and Transpose is a music performance note-taking app designed for musicians familiar with chords. It enables users to effortlessly maintain and transpose songs to any key with a simple button press. The app intelligently separates chords from lyrics and other notes during transposition, preserving chord modifiers like extensions and alterations.

With support for hundreds of chord types and various modifiers, users can easily customize their note compositions. The app offers the flexibility to adjust font sizes for better visibility on different screen sizes and is compatible with both iPhone and iPad, supporting all orientations. The intuitive "Add Chord" wizard simplifies the process of incorporating chord extensions, keys, and chord types into compositions.