Android 7 - Annoying Popup Toolbox With A Banner Ad. What Is Causing This?

This spam-screen is driving me mad! Does anyone know which app or apps, creates the stupid, useless, annoying garbage of a banner on my phone's screen? I know that it's an app, but I have hundreds of them on my phone. So I haven't been able to figure it out yet. But every time when I press on one of the bottom buttons, near the sides of the screen, this completely worthless popup comes up! I need to figure out who is doing this. So I can delete the app, but also so I can bash the company!