This is an expression that people use near the end of a conversation. For example, if you're visiting someone and you think that it's time for you to leave, you can say:

All right, well I guess I should be going.

"All right" can be said in response to something that another person says. For example:

A: Guys, let's call it a day.

B: All right, we'll pick it back up in the morning.

But you can also say "all right" on its own to show that you're ready to end the conversation, even if no one else has said anything.