I have a flip phone that my parents use to contact me. Since only my parents contact me on it, I generally assume that if my phone dings, it's kinda important that I read it. For example, this past afternoon, my phone dinged in the middle of a conversation with my friend's parent, and I needed to check it because my parents were coming at some point to pick me up.
What's a polite way to check one's phone in such a situation?