The 4.5 version of Musition for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this Mac application is Rising Software Australia Pty Ltd.
According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. The program lies within Audio & Video Tools, more precisely Music Production.
From the developer:
Musition is a complete music theory and musicianship package, suitable for students of all ages. Interactive drill based teaching makes learning music theory fundamentals fun and easy!
You may want to check out more Mac applications, such as Musition 4, which might be related to Musition.