Augusta Sportswear 1920 Tri-Color Drawstring Backpack is excellent for gym. It has place for everything you need like change of clothes, sneakers, towel, etc.
Nike Team Training Gymsack is good gym bag. It can be used for basketball gear and has three separate compartments. You can put towel, gym clothes, shoes, etc. Bag can be used for multiple of purposes.
World Traveler Polka Dot Travel Tote Bag is a perfect size of the bag. You can put wallet, cell phone, change of clothes. Bag has side pocket for a water bottle or some other things. It great for the traveling.