premise: The IPhone 4 is only a stationary personal computer.
hypothesis: The iPhone 4 is a smartphone that was designed and marketed by Apple Inc. . The iPhone 4 introduced a new hardware design to the iPhone family , which Apple 's CEO Steve Jobs touted as the thinnest smartphone in the world at the time ; it consisted of an uninsulated stainless steel frame which doubles as an antenna , with internal components situated between chemically strengthened aluminosilicate glass . The iPhone 4 was also the first iPhone to include a front-facing camera , and the first to be released in a version for CDMA networks , ending AT&T 's period as the exclusive carrier of iPhone products in the United States . The iPhone 4 spent the longest time as Apple 's flagship iPhone model at fifteen months , and had the longest lifespan of any iPhone ever produced , spanning close to four years and available in some developing countries until early 2015 .