Ao Nang is Krabi's main beach base: convenient, crowded, commercial, and still hard to beat if you want easy access to the Andaman coast. It is not the loveliest beach in the province, but it has the boats, restaurants, dive shops, tour desks, and transport links that make the area work.
The best reason to stay here is not only Ao Nang Beach itself, but what leaves from it. Longtail boats run south to Railay Beach and Phra Nang Beach, while island trips go out to Ko Poda, Chicken Island, and the smaller sandbar islands.
Ao Nang is busiest around sunset, when the limestone cliffs turn gold and the beachfront fills with walkers. If you want solitude, stay elsewhere. If you want a practical base with beautiful scenery within easy reach, Ao Nang does the job very well.