Let's start cooking!
Preheat the oven to 180 °C (350 °F). In a bowl, mix the apples with the brown sugar, maple syrup, lemon juice and cinnamon.
Butter a 25 cm x 20 cm (10" x 8") baking dish, then pour in the mixture. Put the biscuits into a sealable plastic bag and crush into coarse crumbs using a rolling pin.
In a separate bowl, combine the biscuit crumbs with the oats, butter, flour and brown sugar until forming a crumbly texture. Layer the crumble over the apple mixture, before lightly pressing. Cook in the oven for 50 minutes to 1 hour, until golden brown on top.