From a composers point of view of using this app for more than 3 weeks now, it gets the job done (fast!). I mean, I dont like to use an app where I "have" to use my keyboard or mouse to input the musical notations in; it would take me hours to finish just a page of a specific musical piece (on Logic Pro X and PreSonus). For this app itself, I can think and write my music at the same time; its so freakin convenient.
However, on the contrary of the quality of the app, its not very well designed. After a few bars of inputting my notes, the app freezes for few minutes (and then I have to either wait or to close the app). There are cases where if I have too many instruments or if I write too quick, the app simply crashes. The good thing is it saves my work when the app closes (even when it crashes). The bad thing, of course is the crash itself is notoriously annoying. Therefore, there are some improvement needed! I await for future stable updates!