Version: 2017.3

Application.runInBackground

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public static bool runInBackground ;

Description

Should the player be running when the application is in the background?

Default is false (application pauses when it is in the background).

Note: This property is ignored on Android and iOS.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { void Example() { Application.runInBackground = true; } }