[Rey_a]

I knew there had to be a valid reason for you to make the switch to 'material'. Thanks for explaining!

About the blue: I understand your reasoning concerning readability. But looking at tapatalk app, they use the same blue for tab selection and in the (background) cercle for the pen. The pen is also white and I think readability there is still quite good.
You currently use still a third variation of blue for the the text in (amoung others) the exit screen and there, readability is a little less (probably helped by the not really black background)
Personally I find all those different colour variations of blue to be a little distracting. Having 'Tab selection', 'Edit options' background and currently blueish texts appearing in the same kind of blue (the one of the tab selection) would feel more relaxed, to me at least.
(come to think of it, the blue title bar in the setlist detail library screen could also be changed to this 'Tab Selection' blue).

Looking at Tapatalk and Evernote as examples they seeme to have choosen an icon colour to appear on several levels in their application (orange for Tapatalk, green for Evergreen). And they stick to that same variation of the colour, which give the G.U.I (graph. user interface) a typical Tapaltalk or Evernote look and feel.
Also they did not go for the most hard/contrasting colour but a bit more soft watercoloury variation, which I also seem to find in Gmail app for example.

Just my two cents worth though, I am not a graphical / easthetical professional or so :-)