Unity Game for Universal Windows 10 Platform - multiple devices confusion?

Question

I am going to develop simple 2D game in Unity for Universal Windows Platform (Windows 10) and I am confused with these multiple devices.

Windows 10 Mobile phone is absolutely different from large desktop so: How to make menu gui and game user interface compatible with all devices?

Answer 1

Add a Canvas Scaler component to the Canvas. This will automatically resize the elements, to match the current resolution. You can even change it runtime to resize all the UI elements at once.
Set the scale mode to Scale with screen size.