This larger cousin to the iPhone 6 bumps the screen size to 5.5 inches. Compared to the iPhone 5s it also improves the camera and processor, adds NFC, and switches to a thinner, more rounded design.
iPhone 6 Plus. Apart from battery, screen, and small camera differences, the iPhone 6 and 6 Plus have identical hardware: 802.11ac Wi-Fi support, Voice over LTE with Verizon, AT&T, T-Mobile ...
At 6.3 inches, it would be in between the size of the 6.1-inch iPhone 15 and the 6.7-inch iPhone 15 Plus. However, this year there may be only one non-Pro model in Apple's lineup (see below).