In a large bowl, toss the potatoes with olive oil, smoked paprika, garlic granules, and season with salt and pepper. Make sure that the potatoes are well coated.
Place in the Air Fryer basket, and roast at 380°F (195°C) for 10 minutes. Flip the potatoes, and roast for 10 more minutes.
You don't have to preheat the Air Fryer, but if you have time, then preheating it for 5 minutes will result in crispier potatoes.
If you're using starchy potatoes, then it helps to soak them in cold water for 10-15 minutes prior to roasting them to get rid of the extra starch. Make sure to pat dry the potatoes, as otherwise, they will steam rather than roast.
Use tongs or turner to flip the potatoes halfway through, shaking the basket might break some of the potatoes and won't flip them all.