Place flour, brown sugar, cinnamon and salt in a small bowl and mix together.  Stir in oats.

Chop butter in small pieces and add to bowl.

Use clean hands to gently press butter between your fingers, creating a crumble mixture.  Stop when you have small pieces of butter still visible.

Remove tray or basket from air fryer and place mixture directly in.

Cook for 5 minutes at 350, then lightly and gently toss mixture as to not break up the clumps forming.  Bake for another 5 minutes.  Mixture should be lightly golden brown and toasted. *NOTE:  keep in mind that all air fryers cook differently!  This is the timing that worked on mine.  Keep an eye on your crumble and take it out if it's getting too toasty. 

Let cool to just warm, or completely cool.

To serve, toss your favorite diced fresh fruit or berries in a little sugar and divide into bowls.  Drizzle fruit with cream and then pile crumb topping on top.