First of all it is not really worth looking around in all the souks. All you get in ALL shops is Nokia. There is cellphone souk, right in front of Souk Waquif. 30-40 stores. All of them sell... right, Nokia. In Carrefour you'll at least get a good selection of brands, as well some promotional prices. Go to the new Carrefour in Villagio, for some reason it tends to be cheaper than the one in City Centre, and better stocked.