Announced back in October, Walmart is now offering an exclusive unlimited 4G data, text, and 100 minute smartphone plan on T-Mobile without a contract for only $30/month. It includes unlimited web, with the first 5 GB at up to 4G speeds; unlimited text; and 100 minutes of talk, with 10 cents per minute after the first 100 minutes. The plan will be sold exclusively in-store at more than 2,200 Walmart stores and online at walmart.com.