Finally managed to make call notifications visible on Android Auto!

app/src/main/AndroidManifest.xml

@@ -194,6 +194,15 @@
                 android:value="Needed to keep app alive to be able to receive messages and calls from third party SIP servers for which push notifications aren't available." />
         </service>
 
+        <service
+            android:name=".telecom.TelecomAndroidAutoService"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="androidx.car.app.CarAppService"/>
+                <category android:name="androidx.car.app.category.CALLING"/>
+            </intent-filter>
+        </service>
+
         <!-- Receivers -->
 
         <receiver android:name=".core.CorePushReceiver"

app/src/main/java/org/linphone/telecom/TelecomAndroidAutoService.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2010-2024 Belledonne Communications SARL.
+ *
+ * This file is part of linphone-android
+ * (see https://www.linphone.org).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.linphone.telecom
+
+import android.content.pm.ApplicationInfo
+import androidx.car.app.CarAppService
+import androidx.car.app.validation.HostValidator
+import org.linphone.R
+
+class TelecomAndroidAutoService : CarAppService() {
+    override fun createHostValidator(): HostValidator {
+        return if ((applicationInfo.flags and ApplicationInfo.FLAG_DEBUGGABLE) != 0) {
+            HostValidator.ALLOW_ALL_HOSTS_VALIDATOR
+        } else {
+            HostValidator.Builder(applicationContext)
+                .addAllowedHosts(R.array.hosts_allowlist_sample_copy)
+                .build()
+        }
+    }
+}

app/src/main/res/values/strings.xml

@@ -853,4 +853,17 @@
     <string name="content_description_ldap_delete">Delete this LDAP configuration</string>
     <string name="content_description_ldap_save">Save LDAP configuration</string>
     <string name="content_description_play_call_recording">Plays the call recording</string>
+
+    <!-- Copy of private hosts_allowlist_sample in androidx.car.app:app:1.7.0-beta01, as they recommend it.
+     I removed android automotive hosts to only keep Android Auto ones for now -->
+    <string-array name="hosts_allowlist_sample_copy" translatable="false">
+        <item>fdb00c43dbde8b51cb312aa81d3b5fa17713adb94b28f598d77f8eb89daceedf,
+            com.google.android.projection.gearhead</item>
+
+        <item>70811a3eacfd2e83e18da9bfede52df16ce91f2e69a44d21f18ab66991130771,
+            com.google.android.projection.gearhead</item>
+
+        <item>1975b2f17177bc89a5dff31f9e64a6cae281a53dc1d1d59b1d147fe1c82afa00,
+            com.google.android.projection.gearhead</item>
+        </string-array>
 </resources>

app/src/main/res/xml/automotive_app_desc.xml

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <automotiveApp>
     <uses name="notification" />
+    <uses name="template"/>
 </automotiveApp>