Verizon Communications will give subscribers who trade in an old iPhone a free iPhone 6 in exchange for a two-year contract, the country’s largest wireless carrier announced hours after Apple Inc unveiled the widely anticipated device. The announcement came as critics speculated that Apple’s newest phone, starting at $199 with a two-year contract, would not be competitive as more carriers eliminate contracts and unbundle service charges from the cost of devices. Analysts say that by making the cost of devices more transparent, equipment financing plans make expensive handsets like the iPhone less appealing. On the other hand, the plans allow customers to pay for devices in installments, making pricy devices like the iPhone more accessible. Customers who trade in an iPhone 4, 4s, 5, 5c or 5s in working condition will receive a $200 gift card to pre-order the 16-gigabyte version of the newer model.