In Swedish äppelpaj, breadcrumbs are often used instead of some or all of the flour.
This style is closely related to Swedish smulpaj, or crumb pie, a fruit dessert topped with a buttery mixture rather than enclosed in a traditional pastry shell. Swedish versions vary widely: some use wheat flour, others use rolled oats, and some use dry breadcrumbs for a crisp, toasted topping.
Breadcrumbs are especially useful because they absorb fruit juices while becoming browned and crunchy in the oven. They are not the same as almond flour, rice flour, or cornmeal, which may appear in specialty or gluten-free recipes but are not the characteristic substitute in this context.
The Swedish name is usually written äppelpaj: äpple means “apple,” and paj means “pie.” When the dessert is specifically called äppelsmulpaj, the crumb topping is central to the dish rather than an optional variation.