Shaders in Stack(Ketchapp)

Does anyone by any chance know how to make shaders found on blocks in popular game called Stack made by Ketchapp company?

I kinda assume that a lot of that depends on lighting and global illumination.

EDIT: So, I've done some researching, and I think this is called flat shading, no? Nevertheless, I no longer require your help, I've managed to purchase one from the Unity Store. It's called "Minimalist - Lowpoly Flat/Gradient Shader".

Here's a picture for reference:

 

Thanks for sharing

 

I've updated my post. Now you have more information about the shading package I've purchased.