New iPhone 4s are available for purchase on Amazon and Best Buy. Both retailers offer a variety of models with different service provider compatibilities. Users can also buy an unlocked iPhone 4 to work on any compatible provider network.
Glyde, an online markeplace for used electronics, also has a large selection of used iPhone 4s. Similar to Amazon and Best Buy, the models are categorized by storage capacity and color, but do not include a SIM card. Ebay also offers a huge inventory of iPhone 4s, many of which are unlocked. Because they come without a service contract with a specific provider, these unlocked phones typically are higher in cost.