A Google engineer, called Hiroshi Lockheimer, has revealed what the mysterious X and P in the Nexus 5X and Nexus 6P stand for.
The Google team which built the Nexus 2015 devices, conducted an Ask Us Anything session over at Reddit’s AMA sub/
And one of the questions put to Lockheimer was about the mysterious letters, to which he replied:
X for the core of the Nexus brand (plus it sounds cool!), P for premium.
There you go, X means Nexus and P means Premium. The latter sounds a bit odd, especially as it signifies the more powerful specs of the Huawei device, and kind of makes it sound like the Nexus 5X is a cheap phone.
But the letter may have been added to differentiate the device from the Nexus 6 from last year.