Okay, here is what I found. I can download the Softonics one on my phone and NS. But, as soon as I opened the app it directed me to some updated app called “Next TV”. This would not load on my NS. On my phone I just did a Google search for Next TV and I downloaded the app to my phone. Now with this app installed I can cast to my TV in full screen. It has the exact same channels as the USTVGO app.
I just don’t like using my phone as a projector because of the battery drain, but the quality of the audio/visual is good.
If I could figure a way to go full screen on the USTVGO app then that would be the only one I would keep.
So as it is I have the USTVGO app on the Nvidia, and the Next TV app on my phone. The USTVGO app is more convenient, but the Next TV app allows me a full screen making for a more enjoyable experience.