The pale blue of a clear sky is traditionally read as calm, openness and peace of mind. It also carries gentleness and a sense of fresh air after strain.
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.