How to open activity (incoming voip call) in Android 10 : <p>In Android 10 there apply new restrictions for apps.
We can no longer start an activity from background. While this may be fine for the majority of apps, it's a killing blow for voip-apps that need to show an incoming call after a push notification arrived.</p>

<p>According to this <a href="https://developer.android.com/guide/components/activities/background-starts" rel="noreferrer">https://developer.android.com/guide/components/activities/background-starts</a> there is a list of conditions that can be met to still allow opening an activity, but tbh I do not understand that fully (non-english-native here).</p>

<p><em>What I definitely know, is:</em></p>

<ul>
<li><p>I do not have any running activity, task, backstack and the like</p></li>
<li><p>The app is NOT EVEN RUNNING</p></li>
</ul>

<p><em>What I need to achieve:</em></p>

<ul>
<li>The FCM service of the app receives a push from our server and shall present the incoming call screen (over lock screen and all - just as it did with android 9 and below)</li>
</ul>

<p>What can I do to open an activity for an incoming voip call in android 10?
Over the lockscreen and all, just as a normal user would expect from a PHONE app.</p>

<p>Thanks in advance for any hints.</p>
