I speak French much better with GBoard, because it spells better than I do. It also has a pretty good sense of grammar: it will often autocomplete the correct ending of a verb. (It feels like cheating to use it with Duolingo.)

Of course I speak only simple French, and those are the cases where its primitive learning is most apt. When I speak English, its suggestions are less useful, because I use a much wider vocabulary and more sophisticated sentence structure.