Understanding Orthographic SizeHow to get the perfect device zoom in Unity

Source Code For Vertical Fit

Use this code for when you want the the left and right edges of the area to touch the camera edges.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraScript : MonoBehaviour {
    public SpriteRenderer rink;

	// Use this for initialization
	void Start () {
        Camera.main.orthographicSize = rink.bounds.size.x * Screen.height / Screen.width * 0.5f;
	}
}

Source Code For Horizontal Fit

Use this code for when you want the top and bottom edges of the area to touch the camera edges.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraScript : MonoBehaviour {
    public SpriteRenderer rink;

	// Use this for initialization
	void Start () {
        Camera.main.orthographicSize = rink.bounds.size.y / 2;
	}
}

Source Code For Entire Fit

Use this code when you want to calculate so the entire area is in view.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraScript : MonoBehaviour {
    public SpriteRenderer rink;

	// Use this for initialization
	void Start () {
        float screenRatio = (float)Screen.width / (float)Screen.height;
        float targetRatio = rink.bounds.size.x / rink.bounds.size.y;

        if(screenRatio >= targetRatio){
            Camera.main.orthographicSize = rink.bounds.size.y / 2;
        }else{
            float differenceInSize = targetRatio / screenRatio;
            Camera.main.orthographicSize = rink.bounds.size.y / 2 * differenceInSize;
        }
	}
}