The issue of phones (or how to politely read a text)

Question

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?

Answer 1

You can just say it is a text/call you were expecting from a family member. The reason this works is due to 2 factors

1. You bring up the fact that you are about to check your phone, this is not considered rude compared with just going for your phone and interrupting whatever you were doing.
2. A call from a family member is a perfectly valid reason to pick up the phone, no one would hold it against you.

Answer 2

In addition to @moonpire00's answer, I think that it would be good to frame this as a question, rather than assuming their consent.

Sorry, do you mind if I take/read this? It's _______ (valid reason why it is a particularly important message)

Pretty much everyone will consent, but it gives people a chance to voice their opinion, and shows more respect.