Not sure if there is a functionality to this but on android I seem to have a sliding bar at the bottom of screen whenever there is text on screen.
Additionally, and maybe related, I am unsure of how to skip. I have the setting that should enable me to skip already seen text - but I see no button to do this. I tried dragging the slider incase that was related but it did nothing. I also tried enabling it to let me skip even unseen text to test if it just didn't recognize i had seen it- still didn't show anything