Place the apples in the Instant Pot and top with the cinnamon, nutmeg, maple syrup, caramel syrup, and water. Stir together well until a liquid consistency is reached and the apples are coated.
Create the topping: In a microwave-safe bowl, melt the butter, then add the brown sugar, oats, flour, and salt. Mix well and pour over the apple mixture in the pot.
Secure the lid, move the valve to the sealing position, and hit Manual or Pressure Cook on High Pressure for 2 minutes. When done, allow a full natural release (this will take 20–30 minutes).
Serve right out of the pot, topped with vanilla ice cream and some more caramel sauce, if desired.