diff --git a/res/layout/chat_device_cell.xml b/res/layout/chat_device_cell.xml
new file mode 100644
index 000000000..8838da643
--- /dev/null
+++ b/res/layout/chat_device_cell.xml
@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/layout"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:gravity="center_vertical"
+    android:background="@color/colorH"
+    android:orientation="vertical">
+
+    <RelativeLayout
+        android:layout_width="match_parent"
+        android:layout_height="40dp"
+        android:layout_margin="5dp"
+        android:gravity="center_vertical">
+
+        <RelativeLayout
+            android:id="@+id/avatar"
+            android:visibility="invisible"
+            android:layout_width="wrap_content"
+            android:layout_height="match_parent"
+            android:gravity="center">
+
+            <include layout="@layout/contact_avatar"/>
+
+        </RelativeLayout>
+
+        <TextView
+            android:id="@+id/name"
+            style="@style/font6"
+            android:lines="1"
+            android:ellipsize="end"
+            android:maxLines="1"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_toRightOf="@+id/avatar"
+            android:layout_toLeftOf="@+id/security_level"
+            android:layout_marginLeft="10dp"
+            android:layout_marginRight="5dp"
+            android:layout_centerVertical="true"/>
+
+        <ImageView
+            android:id="@id/security_level"
+            android:src="@drawable/security_alert_indicator"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignParentRight="true"
+            android:layout_centerVertical="true"
+            android:layout_marginRight="10dp"/>
+
+    </RelativeLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/res/layout/chat_device_group.xml b/res/layout/chat_device_group.xml
new file mode 100644
index 000000000..c79000bc0
--- /dev/null
+++ b/res/layout/chat_device_group.xml
@@ -0,0 +1,51 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/layout"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:gravity="center_vertical"
+    android:background="@color/colorH"
+    android:orientation="vertical">
+
+    <RelativeLayout
+        android:layout_width="match_parent"
+        android:layout_height="40dp"
+        android:layout_margin="10dp"
+        android:gravity="center_vertical">
+
+        <RelativeLayout
+            android:id="@+id/avatar"
+            android:layout_width="wrap_content"
+            android:layout_height="match_parent"
+            android:gravity="center">
+
+            <include layout="@layout/contact_avatar"/>
+
+        </RelativeLayout>
+
+        <TextView
+            android:id="@+id/name"
+            style="@style/font6"
+            android:lines="1"
+            android:ellipsize="end"
+            android:maxLines="1"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_toRightOf="@id/avatar"
+            android:layout_toLeftOf="@+id/dropdown"
+            android:layout_marginLeft="10dp"
+            android:layout_marginRight="5dp"
+            android:layout_centerVertical="true"/>
+
+        <ImageView
+            android:id="@id/dropdown"
+            android:src="@drawable/chevron_list_close"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignParentRight="true"
+            android:layout_centerVertical="true"
+            android:layout_marginRight="10dp"/>
+
+    </RelativeLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/res/layout/chat_devices.xml b/res/layout/chat_devices.xml
index 16ed4378f..87c2b36f6 100644
--- a/res/layout/chat_devices.xml
+++ b/res/layout/chat_devices.xml
@@ -30,6 +30,7 @@
                 android:id="@+id/title"
                 android:text="@string/group_chat_room_devices"
                 style="@style/font6"
+                android:ellipsize="marquee"
                 android:gravity="center"
                 android:layout_width="0dp"
                 android:layout_height="match_parent"
@@ -47,15 +48,11 @@
 
     </RelativeLayout>
 
-    <LinearLayout
+    <ExpandableListView
+        android:id="@+id/devices_list"
+        android:groupIndicator="@null"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:orientation="vertical"
-        android:gravity="center_horizontal"
-        android:layout_below="@id/top">
-
-
-
-    </LinearLayout>
+        android:layout_below="@id/top"/>
 
 </RelativeLayout>
diff --git a/res/layout/contacts_list.xml b/res/layout/contacts_list.xml
index fe9c7c8da..c178d3666 100644
--- a/res/layout/contacts_list.xml
+++ b/res/layout/contacts_list.xml
@@ -126,11 +126,6 @@
 			android:layout_width="match_parent"
 			android:layout_height="match_parent"
 			android:divider="@color/colorE"
-			app:fastScrollEnabled="true"
-			app:fastScrollHorizontalThumbDrawable="@drawable/fast_scroll"
-			app:fastScrollHorizontalTrackDrawable="@drawable/line_drawable"
-			app:fastScrollVerticalThumbDrawable="@drawable/fast_scroll"
-			app:fastScrollVerticalTrackDrawable="@drawable/line_drawable"
 
 			android:dividerHeight="1dp" />
 		
diff --git a/res/values/styles.xml b/res/values/styles.xml
index f04615027..df3ca0266 100644
--- a/res/values/styles.xml
+++ b/res/values/styles.xml
@@ -52,7 +52,7 @@
 
 	<style name="font6" parent="@android:style/TextAppearance.Medium">
 		<item name="android:textColor">@color/colorC</item>
-		<item name="android:textSize">20sp</item>
+		<item name="android:textSize">18sp</item>
 	</style>
 
 	<style name="font7" parent="@android:style/TextAppearance.Medium">
diff --git a/src/android/org/linphone/chat/DeviceAdapter.java b/src/android/org/linphone/chat/DeviceAdapter.java
new file mode 100644
index 000000000..a3775275f
--- /dev/null
+++ b/src/android/org/linphone/chat/DeviceAdapter.java
@@ -0,0 +1,183 @@
+package org.linphone.chat;
+
+/*
+DeviceAdapter.java
+Copyright (C) 2010-2018  Belledonne Communications, Grenoble, France
+
+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 2
+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, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import android.content.Context;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.BaseExpandableListAdapter;
+
+import org.linphone.LinphoneUtils;
+import org.linphone.R;
+import org.linphone.contacts.ContactsManager;
+import org.linphone.contacts.LinphoneContact;
+import org.linphone.core.Address;
+import org.linphone.core.Participant;
+import org.linphone.core.ParticipantDevice;
+import org.linphone.ui.ContactAvatar;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class DeviceAdapter extends BaseExpandableListAdapter {
+    private Context mContext;
+    private List<Participant> mParticipants;
+    private boolean mOnlyDisplayChildsAsGroups;
+
+    public DeviceAdapter(Context context) {
+        mContext = context;
+        mParticipants = new ArrayList<>();
+        mOnlyDisplayChildsAsGroups = false;
+    }
+
+    public void updateListItems(List<Participant> participants, boolean childsAsGroups) {
+        mOnlyDisplayChildsAsGroups = childsAsGroups;
+        mParticipants = participants;
+        notifyDataSetChanged();
+    }
+
+    @Override
+    public View getGroupView(int groupPosition, boolean isExpanded, View view, ViewGroup viewGroup) {
+        if (mOnlyDisplayChildsAsGroups) {
+            ParticipantDevice device = (ParticipantDevice) getGroup(groupPosition);
+
+            DeviceChildViewHolder holder = null;
+            if (view != null) {
+                Object possibleHolder = view.getTag();
+                if (possibleHolder instanceof DeviceChildViewHolder) {
+                    holder = (DeviceChildViewHolder) possibleHolder;
+                }
+            } else {
+                LayoutInflater inflater = LayoutInflater.from(mContext);
+                view = inflater.inflate(R.layout.chat_device_cell, viewGroup, false);
+            }
+            if (holder == null) {
+                holder = new DeviceChildViewHolder(view);
+                view.setTag(holder);
+            }
+
+            Address deviceAddress = device.getAddress();
+            holder.deviceName.setText(deviceAddress.getUriParam("gr")); //TODO
+        } else {
+            Participant participant = (Participant) getGroup(groupPosition);
+
+            DeviceGroupViewHolder holder = null;
+            if (view != null) {
+                Object possibleHolder = view.getTag();
+                if (possibleHolder instanceof DeviceGroupViewHolder) {
+                    holder = (DeviceGroupViewHolder) possibleHolder;
+                }
+            } else {
+                LayoutInflater inflater = LayoutInflater.from(mContext);
+                view = inflater.inflate(R.layout.chat_device_group, viewGroup, false);
+            }
+            if (holder == null) {
+                holder = new DeviceGroupViewHolder(view);
+                view.setTag(holder);
+            }
+
+            Address participantAddress = participant.getAddress();
+            LinphoneContact contact = ContactsManager.getInstance().findContactFromAddress(participantAddress);
+            if (contact != null) {
+                ContactAvatar.displayAvatar(contact, holder.avatarLayout);
+                holder.participantName.setText(contact.getFullName());
+            } else {
+                String displayName = LinphoneUtils.getAddressDisplayName(participantAddress);
+                ContactAvatar.displayAvatar(displayName, holder.avatarLayout);
+                holder.participantName.setText(displayName);
+            }
+
+            holder.groupExpander.setImageResource(isExpanded ? R.drawable.chevron_list_open : R.drawable.chevron_list_close);
+        }
+
+        return view;
+    }
+
+    @Override
+    public View getChildView(int groupPosition, int childPosition, boolean b, View view, ViewGroup viewGroup) {
+        ParticipantDevice device = (ParticipantDevice) getChild(groupPosition, childPosition);
+
+        DeviceChildViewHolder holder = null;
+        if (view != null) {
+            Object possibleHolder = view.getTag();
+            if (possibleHolder instanceof DeviceChildViewHolder) {
+                holder = (DeviceChildViewHolder) possibleHolder;
+            }
+        } else {
+            LayoutInflater inflater = LayoutInflater.from(mContext);
+            view = inflater.inflate(R.layout.chat_device_cell, viewGroup, false);
+        }
+        if (holder == null) {
+            holder = new DeviceChildViewHolder(view);
+            view.setTag(holder);
+        }
+
+        Address deviceAddress = device.getAddress();
+        holder.deviceName.setText(deviceAddress.getUriParam("gr")); //TODO
+        //holder.securityLevel.setImageResource();
+
+        return view;
+    }
+
+    @Override
+    public int getGroupCount() {
+        if (mParticipants.size() == 0) return 0;
+        return mOnlyDisplayChildsAsGroups ? mParticipants.get(0).getDevices().length : mParticipants.size();
+    }
+
+    @Override
+    public int getChildrenCount(int groupPosition) {
+        if (mParticipants.size() == 0) return 0;
+        return mOnlyDisplayChildsAsGroups ? 0 : mParticipants.get(groupPosition).getDevices().length;
+    }
+
+    @Override
+    public Object getGroup(int groupPosition) {
+        if (mParticipants.size() == 0) return null;
+        return mOnlyDisplayChildsAsGroups ? mParticipants.get(0).getDevices()[groupPosition] : mParticipants.get(groupPosition);
+    }
+
+    @Override
+    public Object getChild(int groupPosition, int childPosition) {
+        if (mParticipants.size() == 0) return null;
+        return mParticipants.get(groupPosition).getDevices()[childPosition];
+    }
+
+    @Override
+    public long getGroupId(int groupPosition) {
+        return groupPosition;
+    }
+
+    @Override
+    public long getChildId(int groupPosition, int childPosition) {
+        return childPosition;
+    }
+
+    @Override
+    public boolean isChildSelectable(int groupPosition, int childPosition) {
+        return false;
+    }
+
+    @Override
+    public boolean hasStableIds() {
+        return false;
+    }
+}
diff --git a/src/android/org/linphone/chat/DeviceChildViewHolder.java b/src/android/org/linphone/chat/DeviceChildViewHolder.java
new file mode 100644
index 000000000..a0ebfb24d
--- /dev/null
+++ b/src/android/org/linphone/chat/DeviceChildViewHolder.java
@@ -0,0 +1,36 @@
+package org.linphone.chat;
+
+/*
+DeviceChildViewHolder.java
+Copyright (C) 2010-2018  Belledonne Communications, Grenoble, France
+
+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 2
+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, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import android.view.View;
+import android.widget.ImageView;
+import android.widget.TextView;
+
+import org.linphone.R;
+
+public class DeviceChildViewHolder {
+    public TextView deviceName;
+    public ImageView securityLevel;
+
+    public DeviceChildViewHolder(View v) {
+        deviceName = v.findViewById(R.id.name);
+        securityLevel = v.findViewById(R.id.security_level);
+    }
+}
diff --git a/src/android/org/linphone/chat/DeviceGroupViewHolder.java b/src/android/org/linphone/chat/DeviceGroupViewHolder.java
new file mode 100644
index 000000000..8b377b567
--- /dev/null
+++ b/src/android/org/linphone/chat/DeviceGroupViewHolder.java
@@ -0,0 +1,39 @@
+package org.linphone.chat;
+
+/*
+DeviceGroupViewHolder.java
+Copyright (C) 2010-2018  Belledonne Communications, Grenoble, France
+
+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 2
+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, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import android.view.View;
+import android.widget.ImageView;
+import android.widget.RelativeLayout;
+import android.widget.TextView;
+
+import org.linphone.R;
+
+public class DeviceGroupViewHolder {
+    public RelativeLayout avatarLayout;
+    public TextView participantName;
+    public ImageView groupExpander;
+
+    public DeviceGroupViewHolder(View v) {
+        avatarLayout = v.findViewById(R.id.avatar_layout);
+        participantName = v.findViewById(R.id.name);
+        groupExpander = v.findViewById(R.id.dropdown);
+    }
+}
diff --git a/src/android/org/linphone/chat/DevicesFragment.java b/src/android/org/linphone/chat/DevicesFragment.java
index c5dd62719..4fb744454 100644
--- a/src/android/org/linphone/chat/DevicesFragment.java
+++ b/src/android/org/linphone/chat/DevicesFragment.java
@@ -25,6 +25,7 @@ import android.support.annotation.Nullable;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.ExpandableListView;
 import android.widget.ImageView;
 import android.widget.TextView;
 
@@ -38,11 +39,16 @@ import org.linphone.core.Address;
 import org.linphone.core.ChatRoom;
 import org.linphone.core.ChatRoomCapabilities;
 import org.linphone.core.Core;
+import org.linphone.mediastream.Log;
+
+import java.util.Arrays;
 
 public class DevicesFragment extends Fragment {
     private LayoutInflater mInflater;
     private ImageView mBackButton;
     private TextView mTitle;
+    private ExpandableListView mExpandableList;
+    private DeviceAdapter mAdapter;
 
     private String mRoomUri;
     private Address mRoomAddr;
@@ -61,6 +67,20 @@ public class DevicesFragment extends Fragment {
         mInflater = inflater;
         View view = mInflater.inflate(R.layout.chat_devices, container, false);
 
+        mExpandableList = view.findViewById(R.id.devices_list);
+        mExpandableList.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
+            @Override
+            public boolean onChildClick(ExpandableListView expandableListView, View view, int groupPosition, int childPosition, long l) {
+                return false;
+            }
+        });
+        mExpandableList.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
+            @Override
+            public boolean onGroupClick(ExpandableListView expandableListView, View view, int groupPosition, long l) {
+                return false;
+            }
+        });
+
         initChatRoom();
 
         mTitle = view.findViewById(R.id.title);
@@ -81,6 +101,12 @@ public class DevicesFragment extends Fragment {
         return view;
     }
 
+    @Override
+    public void onResume() {
+        super.onResume();
+        initValues();
+    }
+
     private void initChatRoom() {
         Core core = LinphoneManager.getLcIfManagerNotDestroyedOrNull();
         Address proxyConfigContact = core.getDefaultProxyConfig().getContact();
@@ -108,4 +134,21 @@ public class DevicesFragment extends Fragment {
             mTitle.setText(getString(R.string.chat_room_devices).replace("%s", displayName));
         }
     }
+
+    private void initValues() {
+        if (mAdapter == null) {
+            mAdapter = new DeviceAdapter(getActivity());
+            mExpandableList.setAdapter(mAdapter);
+        }
+        if (mRoom == null) {
+            initChatRoom();
+        }
+
+        boolean onlyDisplayChilds = mRoom.hasCapability(ChatRoomCapabilities.OneToOne.toInt());
+
+        //TODO get list of participants and devices
+        if (mRoom != null && mRoom.getNbParticipants() > 0) {
+            mAdapter.updateListItems(Arrays.asList(mRoom.getParticipants()), onlyDisplayChilds);
+        }
+    }
 }