Kate Hudson -- Did Chris Martin Make Cold Play at Beach?

Kate Hudson was hanging at the beach Saturday with Chris Martin ... which is interesting, right?

Kate split from hubby Matthew Bellamy in December, and Chris has parted ways with Gwyneth Paltrow and moved on to Jennifer Lawrence. So the fun-in-the-sun day in Malibu is kinda curious.

Kate and Chris both brought their kids along, and they've been friends for a long time, but it's still interesting, right?