What does the circle with dots mean? I have this circle with dots that showing up on my apps. Where did it come from and how do I get rid of it? 

I've attached some screenshots:  





It sort of floats on top of it. I can move it around but it doesn't seem to respond to anything. 

Disclaimer: I wrote the app shown but I don't know where this came from and I don't see it on other apps.
It's either Floating Toolbox (Floating Launcher)  which is a shortcut application or the Samsung Galaxy S5/S6 Toolbox. These
Floating Toolbox apps gives you access to your apps from anywhere by pressing the Floating button.

Here is a link to the Floating toolbox app: 

https://play.google.com/store/apps/details?id=com.toolbox.shortcuts

You should be able to disable / uninstall them from settings -> application manager.