Oh, your just not thinking hard enough. One extremely popular area that Apple, MS, and Google have not invaded, but have tried in various forms or fashions, is....... The automobile.
Yeah, Google has some type of "self driving car" thingamajig, but...seriously, who the hell is gonna buy a self driving car.....with Google driving?
Apple, even MS, is into a car...to some degree, but...imagine how much more could accomplished. The tech's there, the softwares there, just, nobody has really come up with any ONE device to integrate it all at one time.
Think tablet...kinda, snaps into place of what is now a stereo.... Plays music, navigates, phone calls through it, with it, dictates notes/documents/emails/whatever while you drive. displays critical info about the car, links with other networks, got that stupid "On" star crap, car alarm integration, comes out when you arrive...wherever, goes with you, take it with you into the office/home, continue from there.
Get back in, hell just install a a forward and rear camera, now you've got a backwards view while backing up (some cars have it standard now) and can record video forward while driving (again, already been invented)
So, so, so much more....
This "device" is in high demand. People are already trying to figure out how to integrate their tablets into their vehicles.
Some of this, yeah, it's already being done...with bits and pieces of technology wired together. But there isn't ONE device that does all these functions. A phone.no. a tablet.no. But...almost.....
Yeah, some car stereos do this, integrate with phones to make calls, play MP3s, even do maps, but really, how hard would it be to get ONE device to do it all? Not very hard at all, and it would replace.....everything.