Those who choose to upgrade in 12 months can avail themselves of iPhone Forever or Galaxy Forever at no additional monthly charge, giving them the chance to switch to the newest Apple or Samsung flagship every year. But those who wait until 18 months to decide can also opt to keep paying for six more months to officially own the phone or to pay for the whole amount in one go.

Sprint Deals, the carrier's other new program, gives new customers the chance to get a line even without a credit check. Those who do get a credit check can lease a low-end to mid-range phone for $5 to $10 a month. On the other hand, those who don't can get a subscription under Sprint Forward's pay-in-advance plans. They need to pay for their phones in advance, as well, but they'll at least get 25 to 50 percent off the devices' retail price.

Sprint has likely been cooking up more and more promotions, since it hasn't been growing as much as it would like these past few years. T-Mobile even eclipsed its customer number under John Legere's leadership. According to reports that surfaced in May, the two carriers are talking about a merger again, except this time, Sprint might have to be the one to surrender the wheel.