As phones are so big these days they require two hands anyway, I reminiscence of Palm Pre/webOS hold-below-the-screen-and-swipe-left-and-right to select exactly the right spot quickly and precisely. I don't remember the rest of the gestures, but at least I don't remember it being as frustrating as Android.
Nokia N9 (Maemo/Meego) also had a few interesting things, as did Ubuntu Touch.
I applaud any research into this though I can't imagine how it will ever beat physical keyboards (other than mind-reading).
I'm glad to see someone else acknowledge this. I get "ok boomer" responses, or people looking at me like I'm growing a second face on my ass. Reactions are even worse than when you mention how shitty Word is as a text editor or word processor.
Structural editing in Lisps is a great convenience -- you manipulate expressions rather than characters.
Schemoid for Android is an admirable example.
Autocompletion based on my previous behaviors would be great, too: If I just googled “The Shining” in Android Chrome then open the Netflix app, Android should know to autofill the Netflix search bar with the completion (and select it, for easy deletion).