In January, T-Mobile, a unit of Deutsche Telekom AG, bought MobileStar Network Corp., a bankrupt Wi-Fi provider that had deployed wireless hotspots in more than 500 Starbucks around the country. Mr. Stanton insists that MobileStar’s problems don’t bode poorly for his own Wi-Fi efforts: MobileStar ran out of money and didn’t have an existing infrastructure to support its Wi-Fi network, he says. T-Mobile has expanded the hotspots to 2,000 locations and recently announced plans to go into 100 airline lounges and 400 Borders bookstores. Mr. Stanton says the company has committed to spending more than $100 million for this nationwide build-out of Wi-Fi hotspots, which he considers money well spent. With T-Mobile’s regular networks, “I can’t get a couple major markets built for $100 million,”