When we first got our LG TV (a fairly cheap 43" LCD with mediocre brightness and WebOS) you could get an app to be the remote control. It was a convenient option when the remote fell under the couch.
They discontinued it for some elaborate "ThinQ" app which was designed to support a huge universe of different devices, and it was no longer something my parents could use.
I miss when phones had IR blasters; it was fun that I could control my old NAD 7100 reciever, which predated consumer smartphones by a good decade plus.
I think the main thing preventing it on the device itself is they haven't thus far needed a large screen to show them on.