Los Carpinteros isn't a beach you choose on looks but it does have easy access for campers and has low-key charm and crystal clear water.
Sandy Playa del Cura beach is where the people who work in south Gran Canaria, local and guiri, go at the weekends.
El Puertillo is a tiny beach with a couple of excellent local seafood restaurants just 15 minutes drives from Las Palmas. It is completely local and oozes charm. Go during the week and you get its little beach, natural swimming pools and restaurants all to yourself.
Melenara Beach is a popular local beach with great seafood restaurants. It is far enough south to escape the cloud that often sits over the north east coast and is the best beach close to the large towns of Telde and Vecindario. Melenara gets no tourists because it's sand is brownish and there are no direct bus links to the resorts.