Stay connected with AT&T in Cos Cob. We offer phones, tablets, smartwatches, and connected devices from all of your favorite brands. We also offer wireless data plans in Cos Cob for every need. Enjoy the flexibility of an Cos Cob prepaid phone plan—with no annual contract and no credit check. Get unlimited text and data with AT&T UNLIMITED ELITE. Get nationwide AT&T 5G service, which comes with all of our unlimited data plans for no extra cost.