Shop around. Don't just look at the big four—Verizon, AT&T, Sprint, and T-Mobile. "There's an entire world of smaller carriers," Segan says. These are known as Mobile Virtual Network Operators, or MVNOs, such as Simple Mobile and H20 Wireless. "They don't actually operate their own network. But if you don't demand the latest high-end smartphone, you'll find that the monthly rates will be very competitive," he says. You can also call up your carrier and say you're considering a cheaper plan from a smaller carrier. Segan says, "They may throw you something to keep you."