Often, streams contain several games/categories. The chapters function on PC is super helpful in determining which categories are in a VOD. For example, I've been catching up on watch party VODs. I like to play the show on my PC and have the streamer and chat replay on my phone. The streamer takes breaks between episodes, which are a pain to skip using the slider. On PC, I can just click the next watch party chapter. Considering this function already exists, it would make sense to port it to the mobile platform.