What does a platypus do with its webbed feet?

Platypuses use their feet for more than two tasks, but the main tasks, apart from walking, are swimming and burrowing.

Platypuses have webbed feet with a retracting webbed membrane which can expose the claws, enabling the platypus to effectively dig burrows. Its claws are used for digging burrows into riverbanks for shelter, and the webbing membrane retracts for that purpose, but spreads between its toes when it needs to swim - which it needs to do to get its food.