Showing touch on Unity editor view.

TouchViewer.cs

public class TouchViewer : MonoBehaviour
{
    /// <summary>
    /// Half-size of cross-hair
    /// </summary>
    public float size = 25;
    
    /// <summary>
    /// How longer lives trails and cross-hairs
    /// </summary>
    public float delayScale = 2f;
    
    void LateUpdate()
    {
        if (Input.touches != null && Input.touches.Length > 0)
            Array.ForEach(Input.touches, ShowTouch);
    }
    
    private void ShowTouch(Touch point) {
        
        Vector2 trail    = point.deltaPosition;
        Vector2 position = point.position;
        
        Color? color = null;
        
        switch (point.phase) {
            
            case TouchPhase.Began:       color = Color.green;   break;
            case TouchPhase.Stationary:
            case TouchPhase.Moved:       color = Color.cyan;    break;
            case TouchPhase.Ended:       color = Color.red;     break;
            case TouchPhase.Canceled:    color = Color.yellow;  break;
        }
        
        if (color.HasValue) {
            
            float time = point.deltaTime * delayScale;
            
            //Trail
            Debug.DrawLine(position, position - trail, color.Value, time);
            
            //Cross-hair
            Debug.DrawLine(position + Vector2.left * size, position + Vector2.right * size, color.Value, time);
            Debug.DrawLine(position + Vector2.up * size,   position + Vector2.down * size,  color.Value, time);
        }
    }
}