I use my air fryer a lot, despite having a fan oven also.

Because the fan circulation is more powerful than in a typical oven, air fryers are really good at is crisping things up, and doing it quickly.

If you ever get take-out and have left over fries, you can put them in the air fryer and they go from fridge-limp to deliciously crisp in just 3 minutes, it resurrects them perfectly. Can’t get results like that in the big oven.