It's usually called apple crumb in the parts of the US I've lived in. It's fruit baked in a pie plate with streusel crumbled over the top, usually served with whipped cream and/or vanilla ice cream. Like a fruit pie without the bottom crust.
Apple is the most common in the US, but in the UK you can get them in all sorts of flavors--apple crumble, pear crumble, plum crumble, strawberry crumble, etc.
Edit: if you're seeing this on QS menus, there is a standard one all across Disney, that is sort of a pocket or purse filled with apple pie filling and streusel on top. I think some of the restaurants call it apple crumble.
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