Whilst I would agree the Apple has not proven itself in the Big Data field.
I would argue that Microsoft is a worthy competitor. They have an excellent Research department and have hardware experience (more so than facebook). They do have the big data chops - enough to put up a search engine, and they have a cloud infrastructure to go with it.
I agree Microsoft is a strong contender given their resources and the fact that they've probably been working on some kind of VR/AR for use with XBox for some time.
And also there's Amazon maybe going at it as the next gen reader or video viewer.
I would argue that Microsoft is a worthy competitor. They have an excellent Research department and have hardware experience (more so than facebook). They do have the big data chops - enough to put up a search engine, and they have a cloud infrastructure to go with it.