Katy Perry & Orlando Bloom Try Co-Parenting on Yacht After Split

Katy Perry and Orlando Bloom seem to be off to a great start in their new relationship dynamic ... because they're making the co-parenting thing look easy ... with an assist from a mega yacht.

The exes were spotted together Sunday on a big boat sailing along Italy's Amalfi Coast ... the first time we've seen them together since we first reported their split.

Katy slipped on a black bikini and Orlando was shirtless aboard a floating paradise ... they played with their 4-year-old daughter, Daisy Dove, and mingled with Jeff Bezos and his new wife, Lauren, who seemingly came aboard for the day.

Orlando looked particularly happy ... smiling and kissing his kid as he lifted her above his head.

Katy missed Jeff and Lauren's big day in Venice -- she was touring in Australia -- but now she's caught up with them in Italy ... and this may explain why Orlando wasn't looking to hook up with anyone at the wedding.

KP and OB broke the silence on their split Wednesday ... their reps said they've slowly shifted from romance to coparenting and planned to be "seen together as a family," and they're clearly living up to that statement.

Katy and Orlando left the yacht briefly ... heading to shore with Daisy Dove for some ice cream and shopping ... and they were all smiles on dry land too.