The big one is going to be schools. They won't die out, but they will be substantially altered and not as dominant as they are today, and that process will take much longer than the uber vs. taxi dynamic will take to play out. So much of modern education is just read, regurgitate, test, even much of a typical undergraduate education falls in that bucket. That sort of education is prime for disruption via interactive educational apps, but the genre hasn't hit it's inflection point moment yet. Nevertheless, sometime in the next 10 to 20 years or so there will be a breakthrough in educational software. Someone will put the pieces together and start making stuff that is universally considered to be excellent, and they will start making a crap ton of money which will fuel a gold rush into making apps using the same ideas. The rest will be history.

Please let it be car dealerships and mattress salespersons. (crosses fingers)

Hotels?.. Travel agencies?.. Car dealerships?

There are too many options to know which one is next.