By default, vertex lighting is forced on mobile for performance reasons. You can disable this by unchecking Force Vertex Shading.mobile in the Project Settings. Also, you need to enable Allow Hidpi in the project settings to allow the game to render at native resolution (again at a performance cost).
Also, since you're using pixel art textures, you'll want to reimport them with lossless compression by selecting them in the FileSystem dock, going to the Import dock, setting compression to Lossless then clicking Reimport.