I can play Arknights Endfield for a few hours at a time. I think I've pulled a few 4-hour sessions with it. I do use a controller, as using touch controls is not something I would enjoy for that long. Now, I generally use Samsung DeX to just play it on a gaming setup with my normal monitor and PC peripherals, and I probably did a few 8-hour sessions, but that might be cheating for this topic.
I've played Pokemon Go for hours in the past but it's been a long time since I've done that. These days I find myself playing puzzle games for about an hour or two, but with breaks in between.