Edge to edge on sides is easy enough. The reason why all Android phones have a noticeable bottom chin is because you have to house the display driver (essentially, connections to OLED) somewhere. Apple's idea is to sacrifice part of display and bend it, so the display driver could be underneath the display. It's expensive, requires complicated engineering and manufacturing, and is also patented.

It's way cheaper to just house the driver below the display, as all the other phones are doing.