What color space is iPhone's 7 "Wide color display (P3)"
Ok I've found it. It's DCI-P3 standard:

http://appleinsider.com/articles/16/09/09/apples-wide-color-screen-on-the-iphone-7-will-lead-to-more-faithful-color-reproduction

Most modern android smartphones are already able to display the circle inside the red square, but probably are converting Adobe RGB or DCI-P3 color space to sRBG instead of displaying correctly the original one.

Comparison sRGB vs Adobe RGB vs DCI-P3: