If you want to give your credit card some exercise, head out to Avenue Jean Medecin in Nice City Centre. Hotels.com travelers also say the area is walkable and has lots of nice beaches. It's also full of great shops and restaurants, so you can spend the afternoon having a wander. Splash some more cash at Promenade des Anglais, Nice Étoile Shopping Center, and Cours Saleya.
You can find out about the history of Nice with a visit to Basilique Notre Dame. Discover the fascinating museums and casinos in this quaint area.