diff --git a/LICENCE b/LICENCE.md
similarity index 99%
rename from LICENCE
rename to LICENCE.md
index 114f15c8e..563755169 100644
--- a/LICENCE
+++ b/LICENCE.md
@@ -1,3 +1,8 @@
+<!--
+ ~ SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
+ ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
+
                       GNU GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 
diff --git a/app/src/generic/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java b/app/src/generic/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
index 88506eb1c..cafaa071d 100644
--- a/app/src/generic/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
+++ b/app/src/generic/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
@@ -1,25 +1,10 @@
 /*
- * Nextcloud Talk application
+ * Nextcloud Talk - Android Client
  *
- * @author Mario Danic
- * @author Marcel Hibbe
- * Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
- * Copyright (C) 2022 Marcel Hibbe <dev@mhibbe.de>
- *
- * 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/>.
+ * SPDX-FileCopyrightText: 2022 Marcel Hibbe <dev@mhibbe.de>
+ * SPDX-FileCopyrightText: 2017-2018 Mario Danic <mario@lovelyhq.com>
+ * SPDX-License-Identifier: GPL-3.0-or-later
  */
-
 package com.nextcloud.talk.utils;
 
 
diff --git a/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml b/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
index c32b784c3..3751cee94 100644
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@@ -1,26 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ /*
-  ~  * Nextcloud Talk application
-  ~  *
-  ~  * @author Mario Danic
-  ~  * Copyright (C) 2017-2020 Mario Danic <mario@lovelyhq.com>
-  ~  *
-  ~  * 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/>.
-  ~  */
-  -->
-  
+  ~ Nextcloud Talk - Android Client
+  ~
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
     <background android:drawable="@drawable/ic_launcher_background"/>
     <foreground android:drawable="@drawable/ic_launcher_foreground"/>
diff --git a/app/src/main/res/values-land/dimens.xml b/app/src/main/res/values-land/dimens.xml
index 374fcf2b7..740d407ff 100644
--- a/app/src/main/res/values-land/dimens.xml
+++ b/app/src/main/res/values-land/dimens.xml
@@ -1,23 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <!-- Default screen margins, per the Android Design guidelines. -->
     <dimen name="activity_horizontal_margin">24dp</dimen>
diff --git a/app/src/main/res/values-night/colors.xml b/app/src/main/res/values-night/colors.xml
index 3d4a0e342..7b4c18f30 100644
--- a/app/src/main/res/values-night/colors.xml
+++ b/app/src/main/res/values-night/colors.xml
@@ -1,28 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Andy Scherzinger
-  ~ @author Daniel Bailey
-  ~ @author Mario Danic
-  ~ Copyright (C) 2021 Andy Scherzinger <info@andy-scherzinger.de>
-  ~ Copyright (C) 2019 Daniel Bailey <db@grappleIT.co.uk>
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2021 Andy Scherzinger <info@andy-scherzinger.de>
+  ~ SPDX-FileCopyrightText: 2019 Daniel Bailey <db@grappleIT.co.uk>
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <color name="colorPrimary">#0082C9</color>
     <color name="colorPrimaryDark">#006AA3</color>
diff --git a/app/src/main/res/values-sw600dp/dimens.xml b/app/src/main/res/values-sw600dp/dimens.xml
index 3619b0852..3b79945c0 100644
--- a/app/src/main/res/values-sw600dp/dimens.xml
+++ b/app/src/main/res/values-sw600dp/dimens.xml
@@ -1,24 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2022 Tim Krüger <t@timkrueger.me>
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
 
     <!-- Custom transition dimensions -->
diff --git a/app/src/main/res/values-v28/arrays.xml b/app/src/main/res/values-v28/arrays.xml
index 235ff002b..3486a2e89 100644
--- a/app/src/main/res/values-v28/arrays.xml
+++ b/app/src/main/res/values-v28/arrays.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <array name="proxy_type_descriptions">
         <item>@string/nc_no_proxy</item>
diff --git a/app/src/main/res/values-v28/defaults.xml b/app/src/main/res/values-v28/defaults.xml
index a79cc44cc..5243ccec6 100644
--- a/app/src/main/res/values-v28/defaults.xml
+++ b/app/src/main/res/values-v28/defaults.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <string name="nc_default_theme">@string/nc_settings_theme_follow_system_key</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-w820dp/dimens.xml b/app/src/main/res/values-w820dp/dimens.xml
index 79c9ceadb..852f74882 100644
--- a/app/src/main/res/values-w820dp/dimens.xml
+++ b/app/src/main/res/values-w820dp/dimens.xml
@@ -1,23 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <!-- Example customization of dimensions originally defined in res/values/dimens.xml
          (such as screen margins) for screens with more than 820dp of available width. This
diff --git a/app/src/main/res/values/arrays.xml b/app/src/main/res/values/arrays.xml
index 914ed67e3..9709fa62d 100644
--- a/app/src/main/res/values/arrays.xml
+++ b/app/src/main/res/values/arrays.xml
@@ -1,26 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ @author Marcel Hibbe
-  ~ Copyright (C) 2022 Marcel Hibbe <dev@mhibbe.de>
-  ~ Copyright (C) 2017 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2022 Marcel Hibbe <dev@mhibbe.de>
+  ~ SPDX-FileCopyrightText: 2017 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <array name="proxy_type_descriptions">
         <item>@string/nc_no_proxy</item>
diff --git a/app/src/main/res/values/attrs.xml b/app/src/main/res/values/attrs.xml
index 9f8bca37a..558b00cd4 100644
--- a/app/src/main/res/values/attrs.xml
+++ b/app/src/main/res/values/attrs.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <declare-styleable name="MicInputCloud">
         <attr name="primaryColor" format="color" />
diff --git a/app/src/main/res/values/bool.xml b/app/src/main/res/values/bool.xml
index b623a68b5..c971c4388 100644
--- a/app/src/main/res/values/bool.xml
+++ b/app/src/main/res/values/bool.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <bool name="value_true">true</bool>
     <bool name="value_false">false</bool>
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index dab4ba2a4..92e643385 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -1,26 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ @author Andy Scherzinger
-  ~ Copyright (C) 2021 Andy Scherzinger <info@andy-scherzinger.de>
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2021 Andy Scherzinger <info@andy-scherzinger.de>
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <color name="colorPrimary">#0082C9</color>
     <color name="colorPrimaryDark">#006AA3</color>
diff --git a/app/src/main/res/values/defaults.xml b/app/src/main/res/values/defaults.xml
index 1f7fc441b..b37be8af9 100644
--- a/app/src/main/res/values/defaults.xml
+++ b/app/src/main/res/values/defaults.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <string name="nc_default_theme">@string/nc_settings_theme_battery_saver_key</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
index 3cdc2baa7..bfc6aa91e 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -1,25 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ @author Tim Krüger
-  ~ Copyright (C) 2022 Tim Krüger <t@timkrueger.me>
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2022 Tim Krüger <t@timkrueger.me>
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <!-- Default screen margins, per the Android Design guidelines. -->
     <dimen name="activity_horizontal_margin">16dp</dimen>
diff --git a/app/src/main/res/values/setup.xml b/app/src/main/res/values/setup.xml
index 34ca74546..2f366612d 100644
--- a/app/src/main/res/values/setup.xml
+++ b/app/src/main/res/values/setup.xml
@@ -1,26 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ @author Marcel Hibbe
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~ Copyright (C) 2022-2023 Marcel Hibbe <dev@mhibbe.de>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2022-2023 Marcel Hibbe <dev@mhibbe.de>
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <!-- Set before a release -->
     <string name="nc_talk_database_encryption_key" translatable="false">HvAfHtAy/QdFYqAWFFXa1VV_Iv6ZQ1.tf5swMc^45wS_vz=Wm[oyRP5D-</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 90d283075..d5420abdb 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,29 +1,3 @@
-<!--
-  ~ Nextcloud Talk application
-  ~
-  ~ @author Mario Danic
-  ~ @author Andy Scherzinger
-  ~ @author Marcel Hibbe
-  ~ @author Tim Krüger
-  ~ Copyright (C) 2022 Tim Krüger <t@timkrueger.me>
-  ~ Copyright (C) 2022-2024 Marcel Hibbe <dev@mhibbe.de>
-  ~ Copyright (C) 2021 Andy Scherzinger <info@andy-scherzinger.de>
-  ~ Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
 <!--
 How to work with translations as a developer:
 - Only add new translations to values/stings.xml, don't do this for other languages (it will be done via transifex).
@@ -41,6 +15,13 @@ How to translate with transifex:
 -->
 
 <resources>
+<!--
+  ~ Nextcloud Talk - Android Client
+  ~
+  ~ SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
+
     <!-- Common -->
     <string name="nc_yes">Yes</string>
     <string name="nc_no">No</string>
diff --git a/app/src/main/res/xml/auth.xml b/app/src/main/res/xml/auth.xml
index 3078c74d0..88efd442b 100644
--- a/app/src/main/res/xml/auth.xml
+++ b/app/src/main/res/xml/auth.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
-  ~  
-  ~ @author Tobias Kaminsky
-  ~ Copyright (C) 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
-  ~  
-  ~ 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/>.
-  -->
-
+  ~ Nextcloud Talk - Android Client
+  ~
+  ~ SPDX-FileCopyrightText: 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <account-authenticator xmlns:android="http://schemas.android.com/apk/res/android"
     android:accountType="com.nextcloud.talk2"
     android:icon="@mipmap/ic_launcher"
diff --git a/app/src/main/res/xml/backup_config.xml b/app/src/main/res/xml/backup_config.xml
index f2de38318..4be2fa975 100644
--- a/app/src/main/res/xml/backup_config.xml
+++ b/app/src/main/res/xml/backup_config.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017 Mario Danic
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <full-backup-content>
     <!-- Exclude specific shared preferences that contain GCM registration Id -->
 </full-backup-content>
diff --git a/app/src/main/res/xml/chip_others.xml b/app/src/main/res/xml/chip_others.xml
index 534bf454b..5d2350f3a 100644
--- a/app/src/main/res/xml/chip_others.xml
+++ b/app/src/main/res/xml/chip_others.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2018 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <chip xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:textAppearance="@style/ChipIncomingTextAppearance"
diff --git a/app/src/main/res/xml/chip_you.xml b/app/src/main/res/xml/chip_you.xml
index ae1c862ad..f38cc34d3 100644
--- a/app/src/main/res/xml/chip_you.xml
+++ b/app/src/main/res/xml/chip_you.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2018 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <chip xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:textAppearance="@style/ChipOutgoingTextAppearance"
diff --git a/app/src/main/res/xml/contacts.xml b/app/src/main/res/xml/contacts.xml
index 830443fc1..067059725 100644
--- a/app/src/main/res/xml/contacts.xml
+++ b/app/src/main/res/xml/contacts.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
-  ~  
-  ~ @author Tobias Kaminsky
-  ~ Copyright (C) 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
-  ~  
-  ~ 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/>.
-  -->
-
+  ~ Nextcloud Talk - Android Client
+  ~
+  ~ SPDX-FileCopyrightText: 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <ContactsAccountType xmlns:android="http://schemas.android.com/apk/res/android">
     <ContactsDataKind
         android:mimeType="vnd.android.cursor.item/vnd.com.nextcloud.talk2.chat"
diff --git a/app/src/main/res/xml/file_provider_paths.xml b/app/src/main/res/xml/file_provider_paths.xml
index 70b5bfb0d..5cab30c98 100644
--- a/app/src/main/res/xml/file_provider_paths.xml
+++ b/app/src/main/res/xml/file_provider_paths.xml
@@ -1,23 +1,9 @@
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017-2019 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <paths>
     <files-path
         name="files"
diff --git a/app/src/main/res/xml/network_security_config.xml b/app/src/main/res/xml/network_security_config.xml
index 6997f0861..6f9486e58 100644
--- a/app/src/main/res/xml/network_security_config.xml
+++ b/app/src/main/res/xml/network_security_config.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Mario Danic
-  ~ Copyright (C) 2017 Mario Danic
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2017 Mario Danic <mario@lovelyhq.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <network-security-config>
     <base-config cleartextTrafficPermitted="true">
         <trust-anchors>
diff --git a/app/src/main/res/xml/syncadapter.xml b/app/src/main/res/xml/syncadapter.xml
index 940c3419c..bab4e9080 100644
--- a/app/src/main/res/xml/syncadapter.xml
+++ b/app/src/main/res/xml/syncadapter.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
-  ~  
-  ~ @author Tobias Kaminsky
-  ~ Copyright (C) 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
-  ~  
-  ~ 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/>.
-  -->
-
+  ~ Nextcloud Talk - Android Client
+  ~
+  ~ SPDX-FileCopyrightText: 2020 Tobias Kaminsky <tobias.kaminsky@nextcloud.com>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <sync-adapter
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:accountType="com.nextcloud.talk2"
diff --git a/app/src/qa/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java b/app/src/qa/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
index 1625c9867..94778d817 100644
--- a/app/src/qa/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
+++ b/app/src/qa/java/com/nextcloud/talk/utils/ClosedInterfaceImpl.java
@@ -1,25 +1,10 @@
 /*
- * Nextcloud Talk application
+ * Nextcloud Talk - Android Client
  *
- * @author Mario Danic
- * @author Marcel Hibbe
- * Copyright (C) 2017-2018 Mario Danic <mario@lovelyhq.com>
- * Copyright (C) 2022 Marcel Hibbe <dev@mhibbe.de>
- *
- * 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/>.
+ * SPDX-FileCopyrightText: 2022 Marcel Hibbe <dev@mhibbe.de>
+ * SPDX-FileCopyrightText: 2017-2018 Mario Danic <mario@lovelyhq.com>
+ * SPDX-License-Identifier: GPL-3.0-or-later
  */
-
 package com.nextcloud.talk.utils;
 
 
diff --git a/app/src/qa/res/values/setup.xml b/app/src/qa/res/values/setup.xml
index 4367c61b6..baf2c6c75 100644
--- a/app/src/qa/res/values/setup.xml
+++ b/app/src/qa/res/values/setup.xml
@@ -1,24 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  ~ Nextcloud Talk application
+  ~ Nextcloud Talk - Android Client
   ~
-  ~ @author Andy Scherzinger
-  ~ Copyright (C) 2021 Andy Scherzinger <info@andy-scherzinger.de>
-  ~
-  ~ 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/>.
-  -->
-
+  ~ SPDX-FileCopyrightText: 2021 Andy Scherzinger <info@andy-scherzinger.de>
+  ~ SPDX-License-Identifier: GPL-3.0-or-later
+-->
 <resources>
     <string name="nc_app_name">Talk QA</string>
     <string name="nc_app_product_name">Nextcloud Talk QA</string>
diff --git a/contribute/developer-certificate-of-origin.license b/contribute/developer-certificate-of-origin.license
new file mode 100644
index 000000000..695276532
--- /dev/null
+++ b/contribute/developer-certificate-of-origin.license
@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: 2004, 2006 The Linux Foundation and its contributors
+SPDX-License-Identifier:  CC0-1.0