WEBThe Apple A4 is a 32-bit package on package (PoP) system on a chip (SoC) designed by Apple Inc. and manufactured by Samsung. [4] [5] It was the first SoC Apple designed in-house. The first product to feature the A4 was the first-generation iPad, followed by the iPhone 4, fourth-generation iPod Touch, and second-generation Apple TV. [6]