Harmony Assistant can aid you when you are composing or playing music. Likewise, it lets you print the resulting music scores. Logically, it requires at least basic knowledge of music theory. Good news there is plenty of help available. In this regard, the tool comes with detailed help documentation and shows contextual tips when you hover the mouse over an element. Besides, it is a great idea to watch the tutorial videos available online.
Using the application is almost like working on paper. In this respect, you can make any type of annotations on the sheet. So, in addition to the full range of notes, it is also possible to add symbols, clefs and signatures. Similarly, the tool can perform chord grid calculations as well generate harmony accompaniments and rhythm patterns. Also, you can enable full-page editing to have a clearer view of what you are doing.
I am glad that Harmony Assistant supports actually playing the notes, which serves to monitor what you are doing. Needless to say, this is big help specially when you are not an experienced composer. So, music students are likely to find this feature most useful. It is also quite convenient that the app supports connecting a MIDI instrument and automatically generate notation for the music being played.
In general, Harmony Assistant may be what you are looking for if you are an experienced composer or a student. The app is full of features and you can even add others as it supports using a scripting language. Luckily, there is a trial version you can use without time limits; however, it does not allow saving, printing or exporting scores. Although Harmony Assistant seems to be quite stable, it is my duty to say that it did crash once when I was trying it. You may also want to know that there is a similar cheaper product, called Melody Assistant, which comes from the same developer and has most of Harmony Assistant’s basic features.