Using double buffer and the buffer swap function to end the draw loop, SDL_GL_SwapWindow, when I set the Vsync to Off through:
SDL_GL_SetSwapInterval(0); //returns 0 so the vsync option is set correctly
Looks like the VSync is still on on this device.
I've tested the same code in iOS, other android devices including tablets, pcs and mac with a very simple scene and all of them go from about 60 fps with VSync to +400 without it.
The only device that seems to keep the VSync is the Note 4 because the fps are the same.
This is why I'm asking if there any reason for this. I've looked for the device specifications and checked the display and developer options in case there was some kind of VSync locked option there but I found nothing related to this.
EDIT: Same behaviour with a Samsung Galaxy S4 (VSync won't turn off)
As clarified in comments and documentation, there are drivers and hardware setups that limit the framerate regardless of the vsync configuration/framerate specific management.
In particular, the framerate is limited in most new Android devices.