I have a Z Fold phone and I only use it to provide internet to the device, basically the device has an Android operating system and you can download any app of your choice, in my case I only use 3: YouTube, Netflix and Waze, it works great, it has no latency, that is, when you watch a video or movie and people talk it coincides with the movement of their mouth (hahaha) I hope I have clarified your doubts.Can you cast your phone to the screen or do you have to use the youtube app from the box? Are you using android?