Mascara is read as wanting to be seen and to see boldly. Running mascara is the classic dream image of feelings breaking through a carefully made-up surface.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.