In addition to building visibility in new markets, wireless handset companies use sponsorship to demonstrate their latest products and drive preference in a hyper-competitive category.Below, four sponsorship hot buttons in the wireless handset category.Create brand envy. Manufacturers of high-end phones often use sponsorship to reward current customers and draw new ones.Samsung activated the Lollapalooza music festival with the Galaxy Lounge, a branded experience that offered customers the oppor...