Wash, peel, core and cut apples into medium slices or cubes
Add water, lemon juice and salt to Instant Pot, then add apples and, if using, cinnamon and nutmeg. Give it all a good stir.
Lock on lid and turn pressure valve on lid to SEALING.Choose PRESSURE COOK setting and adjust timer to 7 minutes. Once timer is done, allow pot to run on natural release (timer counts up) for 10-15 minutes, until all pressure is released and pin on lid falls back down.
Open lid, stir and mash apple sauce to your liking with back of spoon, apples will mash very easily. For a super smooth texture you can also use an immersion blender ( I prefer mine slightly chunky, so a spoon is enough).When cool, transfer to a couple of jars and store in fridge (lasts a couple of weeks) or freezer (lasts a few months).