Basic Layout
The main screen of ScalePlay is maybe a bit more complex than that of your average app, but it is very easy to get used to. If we overlook the various tool bars for a second we can identify five large regions. On the top left we have an instrument view, next to it a music notation view. Then there are two matrices or grids in the middle left and right - the next chapter goes into detail regarding these - and finally there is a row with tabs at the bottom that houses our chords.
The above picture show ScalePlay in playback mode. The play button centered right above the chord slider has turned into a square and we can see the green progress bars below our matrices. Looking a bit closer we can also see that the Bb in the piano keyboard is pressed.
Instrument
So this is the instrument view. There is a whole chapter on instruments coming up, so we are not going to get into much detail right now. Suffice to say that there are nine virtual instruments to pick from in ScalePlay. They can be found in Settings.
Music Notation
Again - there is another chapter coming up on music notation. Of interest here is the chevron button right under the word Zera in the picture above. ScalePlay has two of these and they are used to hide the view they are pointing at. So in this case the button would hide the notation view to give the instrument view the full width of the display.
Matrices
These two matrices are the heart and soul of ScalePlay. The next chapter will explain in depth what these things are all about. Again we have a chevron button centered in the top of the image above. In this case the button will hide the matrix to the right.
Chord Slider
Finally we have the chord slider. Chords are being dealt with in their own chapter coming up. Suffice to say that the chord slider is scrollable and chords can be selected when ScalePlay is not in the process of playing back a song.
Now that we have the main parts covered lets take a brief look at those tool bars. It is unusual for an iOS app to have more than one and ScalePlay has 3 of them not counting the navigation bar at the very top.
Top Toolbar
There are essentially 3 toolbars in ScalePlay. This is the top one and located between instrument and notation view. It can move all the way to the right side of the display if the chevron button at the top is tapped. Below that we have circle icon with a dash and a stylized G-clef. Both of these buttons affect the notation view. Below the G-clef button is the tuning button - tapping it shows the tuning window that string instruments can use to detune strings as for open tunings and such. At the bottom we have the instrument reposition button. It centers the piano instrument on middle-c and brings string instruments back to the first position.
Bottom Toolbar
Our bottom toolbar has the now familiar chevron button at the top used to hide the step matrix. Then we have our undo/redo buttons which are grayed out in this instance. The circle button brings up ScalePlay's Quick Edit window which allows to cycle through all chords and edit them. Our settings button below is also grayed out and below that we find the tempo control - a label in the middle of 2 arrows. And finally at the very bottom we have the start/stop button currently in stop mode as our display at the top of the page is showing ScalePlay in play mode.
A quick word about all that graying out of buttons. This is something that most are familiar with from desktop apps, but maybe not so much on iOS. There are simply circumstances where specific operations cannot take place. For example changing the song in play mode or drawing into the matrices. This is for sure something to get used to in ScalePlay, but the alternative would be to toss up warning dialogs which is not that great either.
Center Toolbar
The center toolbar right above the matrices from left to right houses 5 drawing tools, to mirror tools and then the pattern lock selector. Two other options are not visible in play mode. It also includes the TouchPlay button at the very right (grayed out).
Summary
So that was a very quick and superficial dissection of ScalePlay's main interface. At least now we know our way around to a degree, but of course there is much more to it.
Now let's take a look an in-depth look at those matrices.