'blue' means something different in my (geographic) environment, so this posting catched my attention, was thinking the posting refers to the licencing model (-:
I also hit the wrong icon every now and then, same on Windows' task bar..
But I got also a Problem with the FM15 versus FM14 icons, at least on the iPad, I have to really pay attention to pick the 'right' app..
On the Mac's, I created own icons, basically the same as the originals - but with Numbers in the icon. I got FM11, FM12, 2xFM13, 2xFM14, 2xFM15 in my dock (one with, one without Plugins..).
(When working on customer solutions where a customer runs V12, we are running 12 as well, etc.)
A tip from the ancient days of colored borders on manila file folders: 2 stripes of different colors. Even if you're working with only, say, 5 colors, you've got 5 x 5 = 25 possible combinations. And surprisingly your brain is pretty good at associating a given combination with whatever it's supposed to represent.
OK, I take it back!
Now getting confused with Outlook, Safari, Word, Skype, App Store, Clarify, Dropbox, LogMeIn, Jump Desktop, etc. when using Command Tab on my Mac.
Missing the grey and magenta!