diff --git a/app/src/main/java/org/linphone/core/CoreContext.kt b/app/src/main/java/org/linphone/core/CoreContext.kt
index 85dae6730..e6ca53974 100644
--- a/app/src/main/java/org/linphone/core/CoreContext.kt
+++ b/app/src/main/java/org/linphone/core/CoreContext.kt
@@ -177,6 +177,30 @@ class CoreContext(val context: Context) : HandlerThread("Core Thread") {
         Log.i("[Context] Starting call $call")
     }
 
+    fun switchCamera() {
+        val currentDevice = core.videoDevice
+        Log.i("[Context] Current camera device is $currentDevice")
+
+        for (camera in core.videoDevicesList) {
+            if (camera != currentDevice && camera != "StaticImage: Static picture") {
+                Log.i("[Context] New camera device will be $camera")
+                core.videoDevice = camera
+                break
+            }
+        }
+
+        val call = core.currentCall
+        if (call == null) {
+            Log.w("[Context] Switching camera while not in call")
+            return
+        }
+        call.update(null)
+    }
+
+    fun showSwitchCameraButton(): Boolean {
+        return core.videoDevicesList.size > 2 // Count StaticImage camera
+    }
+
     private fun showCallActivity() {
         Log.i("[Context] Starting VoIP activity")
         val intent = Intent(context, VoipActivity::class.java)
diff --git a/app/src/main/java/org/linphone/ui/main/MainActivity.kt b/app/src/main/java/org/linphone/ui/main/MainActivity.kt
index 31c4e3cbc..834fb4093 100644
--- a/app/src/main/java/org/linphone/ui/main/MainActivity.kt
+++ b/app/src/main/java/org/linphone/ui/main/MainActivity.kt
@@ -34,6 +34,8 @@ import org.linphone.databinding.MainActivityBinding
 class MainActivity : AppCompatActivity() {
     companion object {
         private const val CONTACTS_PERMISSION_REQUEST = 0
+        private const val CAMERA_PERMISSION_REQUEST = 1
+        private const val RECORD_AUDIO_PERMISSION_REQUEST = 2
     }
 
     private lateinit var binding: MainActivityBinding
@@ -54,6 +56,8 @@ class MainActivity : AppCompatActivity() {
         if (checkSelfPermission(Manifest.permission.READ_CONTACTS) == PackageManager.PERMISSION_GRANTED) {
             loadContacts()
         }
+        checkSelfPermission(Manifest.permission.CAMERA)
+        checkSelfPermission(Manifest.permission.RECORD_AUDIO)
 
         binding = DataBindingUtil.setContentView(this, R.layout.main_activity)
         binding.lifecycleOwner = this
@@ -68,6 +72,18 @@ class MainActivity : AppCompatActivity() {
                 CONTACTS_PERMISSION_REQUEST
             )
         }
+        if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
+            requestPermissions(
+                arrayOf(Manifest.permission.CAMERA),
+                CAMERA_PERMISSION_REQUEST
+            )
+        }
+        if (checkSelfPermission(Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED) {
+            requestPermissions(
+                arrayOf(Manifest.permission.RECORD_AUDIO),
+                RECORD_AUDIO_PERMISSION_REQUEST
+            )
+        }
     }
 
     override fun onRequestPermissionsResult(
diff --git a/app/src/main/java/org/linphone/ui/voip/fragment/ActiveCallFragment.kt b/app/src/main/java/org/linphone/ui/voip/fragment/ActiveCallFragment.kt
index 30f6ebac0..46b765b98 100644
--- a/app/src/main/java/org/linphone/ui/voip/fragment/ActiveCallFragment.kt
+++ b/app/src/main/java/org/linphone/ui/voip/fragment/ActiveCallFragment.kt
@@ -22,9 +22,11 @@ package org.linphone.ui.voip.fragment
 import android.os.Bundle
 import android.os.SystemClock
 import android.view.LayoutInflater
+import android.view.MotionEvent
 import android.view.View
 import android.view.ViewGroup
 import androidx.lifecycle.ViewModelProvider
+import org.linphone.LinphoneApplication.Companion.coreContext
 import org.linphone.R
 import org.linphone.databinding.VoipActiveCallFragmentBinding
 import org.linphone.ui.main.fragment.GenericFragment
@@ -38,6 +40,33 @@ class ActiveCallFragment : GenericFragment() {
 
     private lateinit var callViewModel: CurrentCallViewModel
 
+    // For moving video preview purposes
+
+    private var previewX: Float = 0f
+    private var previewY: Float = 0f
+
+    private val previewTouchListener = View.OnTouchListener { view, event ->
+        when (event.action) {
+            MotionEvent.ACTION_DOWN -> {
+                previewX = view.x - event.rawX
+                previewY = view.y - event.rawY
+                true
+            }
+            MotionEvent.ACTION_MOVE -> {
+                view.animate()
+                    .x(event.rawX + previewX)
+                    .y(event.rawY + previewY)
+                    .setDuration(0)
+                    .start()
+                true
+            }
+            else -> {
+                view.performClick()
+                false
+            }
+        }
+    }
+
     override fun onCreateView(
         inflater: LayoutInflater,
         container: ViewGroup?,
@@ -101,4 +130,19 @@ class ActiveCallFragment : GenericFragment() {
             binding.chronometer.start()
         }
     }
+
+    override fun onResume() {
+        super.onResume()
+
+        coreContext.postOnCoreThread { core ->
+            core.nativeVideoWindowId = binding.remoteVideoSurface
+            coreContext.core.nativePreviewWindowId = binding.localPreviewVideoSurface
+            binding.localPreviewVideoSurface.setOnTouchListener(previewTouchListener)
+        }
+    }
+
+    override fun onPause() {
+        super.onPause()
+        binding.localPreviewVideoSurface.setOnTouchListener(null)
+    }
 }
diff --git a/app/src/main/java/org/linphone/ui/voip/view/RoundCornersTextureView.kt b/app/src/main/java/org/linphone/ui/voip/view/RoundCornersTextureView.kt
new file mode 100644
index 000000000..728656604
--- /dev/null
+++ b/app/src/main/java/org/linphone/ui/voip/view/RoundCornersTextureView.kt
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2010-2021 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.ui.voip.view
+
+import android.content.Context
+import android.graphics.Outline
+import android.graphics.Rect
+import android.util.AttributeSet
+import android.view.View
+import android.view.ViewOutlineProvider
+import org.linphone.R
+import org.linphone.mediastream.video.capture.CaptureTextureView
+
+class RoundCornersTextureView : CaptureTextureView {
+    private var mRadius: Float = 0f
+
+    constructor(context: Context) : super(context) {
+        mAlignTopRight = true
+        mDisplayMode = DisplayMode.BLACK_BARS
+        setRoundCorners()
+    }
+
+    constructor(context: Context, attrs: AttributeSet) : super(context, attrs) {
+        readAttributes(attrs)
+        setRoundCorners()
+    }
+
+    constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(
+        context,
+        attrs,
+        defStyleAttr
+    ) {
+        readAttributes(attrs)
+        setRoundCorners()
+    }
+
+    private fun readAttributes(attrs: AttributeSet) {
+        context.theme.obtainStyledAttributes(
+            attrs,
+            R.styleable.RoundCornersTextureView,
+            0,
+            0
+        ).apply {
+            try {
+                mAlignTopRight = getBoolean(R.styleable.RoundCornersTextureView_alignTopRight, true)
+                val mode = getInteger(
+                    R.styleable.RoundCornersTextureView_displayMode,
+                    DisplayMode.BLACK_BARS.ordinal
+                )
+                mDisplayMode = when (mode) {
+                    1 -> DisplayMode.OCCUPY_ALL_SPACE
+                    2 -> DisplayMode.HYBRID
+                    else -> DisplayMode.BLACK_BARS
+                }
+                mRadius = getFloat(
+                    R.styleable.RoundCornersTextureView_radius,
+                    context.resources.getDimension(
+                        R.dimen.in_call_round_corners_texture_view_radius
+                    )
+                )
+            } finally {
+                recycle()
+            }
+        }
+    }
+
+    private fun setRoundCorners() {
+        outlineProvider = object : ViewOutlineProvider() {
+            override fun getOutline(view: View, outline: Outline) {
+                val rect = if (previewRectF != null &&
+                    actualDisplayMode == DisplayMode.BLACK_BARS &&
+                    mAlignTopRight
+                ) {
+                    Rect(
+                        previewRectF.left.toInt(),
+                        previewRectF.top.toInt(),
+                        previewRectF.right.toInt(),
+                        previewRectF.bottom.toInt()
+                    )
+                } else {
+                    Rect(
+                        0,
+                        0,
+                        width,
+                        height
+                    )
+                }
+                outline.setRoundRect(rect, mRadius)
+            }
+        }
+        clipToOutline = true
+    }
+
+    override fun setAspectRatio(width: Int, height: Int) {
+        super.setAspectRatio(width, height)
+
+        val previewSize = previewVideoSize
+        if (previewSize.width > 0 && previewSize.height > 0) {
+            setRoundCorners()
+        }
+    }
+}
diff --git a/app/src/main/java/org/linphone/ui/voip/viewmodel/CurrentCallViewModel.kt b/app/src/main/java/org/linphone/ui/voip/viewmodel/CurrentCallViewModel.kt
index 83110755d..4e637efbe 100644
--- a/app/src/main/java/org/linphone/ui/voip/viewmodel/CurrentCallViewModel.kt
+++ b/app/src/main/java/org/linphone/ui/voip/viewmodel/CurrentCallViewModel.kt
@@ -27,6 +27,7 @@ import org.linphone.LinphoneApplication.Companion.coreContext
 import org.linphone.R
 import org.linphone.core.Call
 import org.linphone.core.CallListenerStub
+import org.linphone.core.MediaDirection
 import org.linphone.core.MediaEncryption
 import org.linphone.core.tools.Log
 import org.linphone.ui.main.contacts.model.ContactAvatarModel
@@ -50,14 +51,19 @@ class CurrentCallViewModel() : ViewModel() {
 
     val isMicrophoneMuted = MutableLiveData<Boolean>()
 
+    val fullScreenMode = MutableLiveData<Boolean>()
+
+    // To synchronize chronometers in UI
+    val callDuration = MutableLiveData<Int>()
+
+    // ZRTP related
+
     val isRemoteDeviceTrusted = MutableLiveData<Boolean>()
 
     val showZrtpSasDialogEvent: MutableLiveData<Event<Pair<String, String>>> by lazy {
         MutableLiveData<Event<Pair<String, String>>>()
     }
 
-    val callDuration = MutableLiveData<Int>()
-
     // Extras actions
 
     val isActionsMenuExpanded = MutableLiveData<Boolean>()
@@ -88,11 +94,20 @@ class CurrentCallViewModel() : ViewModel() {
         override fun onEncryptionChanged(call: Call, on: Boolean, authenticationToken: String?) {
             updateEncryption()
         }
+
+        override fun onStateChanged(call: Call, state: Call.State?, message: String) {
+            if (LinphoneUtils.isCallOutgoing(call.state)) {
+                isVideoEnabled.postValue(call.params.isVideoEnabled)
+            } else {
+                isVideoEnabled.postValue(call.currentParams.isVideoEnabled)
+            }
+        }
     }
 
     init {
         isVideoEnabled.value = false
         isMicrophoneMuted.value = false
+        fullScreenMode.value = false
         isActionsMenuExpanded.value = false
         extraActionsMenuTranslateY.value = extraActionsMenuHeight
 
@@ -119,6 +134,14 @@ class CurrentCallViewModel() : ViewModel() {
         }
     }
 
+    fun answer() {
+        // UI thread
+        coreContext.postOnCoreThread {
+            Log.i("$TAG Answering call [$call]")
+            call.accept()
+        }
+    }
+
     fun hangUp() {
         // UI thread
         coreContext.postOnCoreThread {
@@ -154,7 +177,38 @@ class CurrentCallViewModel() : ViewModel() {
         // UI thread
         // TODO: check video permission
 
-        // TODO
+        coreContext.postOnCoreThread { core ->
+            if (::call.isInitialized) {
+                val params = core.createCallParams(call)
+                if (call.conference != null) {
+                    if (params?.isVideoEnabled == false) {
+                        params.isVideoEnabled = true
+                        params.videoDirection = MediaDirection.SendRecv
+                    } else {
+                        if (params?.videoDirection == MediaDirection.SendRecv || params?.videoDirection == MediaDirection.SendOnly) {
+                            params.videoDirection = MediaDirection.RecvOnly
+                        } else {
+                            params?.videoDirection = MediaDirection.SendRecv
+                        }
+                    }
+                } else {
+                    params?.isVideoEnabled = params?.isVideoEnabled == false
+                    Log.i(
+                        "$TAG Updating call with video enabled set to ${params?.isVideoEnabled}"
+                    )
+                }
+                call.update(params)
+            }
+        }
+    }
+
+    fun switchCamera() {
+        coreContext.switchCamera()
+    }
+
+    fun toggleFullScreen() {
+        if (fullScreenMode.value == false && isVideoEnabled.value == false) return
+        fullScreenMode.value = fullScreenMode.value != true
     }
 
     fun toggleExpandActionsMenu() {
diff --git a/app/src/main/res/drawable/shape_answer_button_background.xml b/app/src/main/res/drawable/shape_answer_button_background.xml
new file mode 100644
index 000000000..3b8ff1a6a
--- /dev/null
+++ b/app/src/main/res/drawable/shape_answer_button_background.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="oval">
+    <solid android:color="@color/green_online"/>
+</shape>
\ No newline at end of file
diff --git a/app/src/main/res/layout/voip_active_call_fragment.xml b/app/src/main/res/layout/voip_active_call_fragment.xml
index c34a834e6..9bc263c66 100644
--- a/app/src/main/res/layout/voip_active_call_fragment.xml
+++ b/app/src/main/res/layout/voip_active_call_fragment.xml
@@ -65,13 +65,14 @@
             app:layout_constraintBottom_toBottomOf="@id/call_direction_label"/>
 
         <ImageView
+            android:onClick="@{() -> viewModel.switchCamera()}"
             android:id="@+id/switch_camera"
             android:layout_width="24dp"
             android:layout_height="24dp"
             android:layout_marginEnd="10dp"
             android:adjustViewBounds="true"
             android:src="@drawable/switch_camera"
-            android:enabled="@{viewModel.isVideoEnabled()}"
+            android:visibility="@{viewModel.isVideoEnabled() ? View.VISIBLE : View.GONE}"
             app:layout_constraintTop_toTopOf="@id/call_direction_label"
             app:layout_constraintBottom_toBottomOf="@id/call_direction_label"
             app:layout_constraintEnd_toEndOf="parent"
@@ -148,6 +149,31 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintEnd_toEndOf="parent" />
 
+        <org.linphone.ui.voip.view.RoundCornersTextureView
+            android:id="@+id/remote_video_surface"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:onClick="@{() -> viewModel.toggleFullScreen()}"
+            android:visibility="@{viewModel.isVideoEnabled ? View.VISIBLE : View.GONE, default=gone}"
+            app:layout_constraintBottom_toBottomOf="@id/background"
+            app:layout_constraintEnd_toEndOf="@id/background"
+            app:layout_constraintStart_toStartOf="@id/background"
+            app:layout_constraintTop_toTopOf="@id/background" />
+
+        <org.linphone.ui.voip.view.RoundCornersTextureView
+            android:id="@+id/local_preview_video_surface"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginEnd="10dp"
+            android:layout_marginBottom="40dp"
+            android:visibility="@{viewModel.isVideoEnabled ? View.VISIBLE : View.GONE}"
+            app:alignTopRight="true"
+            app:displayMode="black_bars"
+            app:layout_constraintBottom_toBottomOf="@id/background"
+            app:layout_constraintEnd_toEndOf="@id/background"
+            app:layout_constraintHeight_max="200dp"
+            app:layout_constraintWidth_max="200dp" />
+
         <include
             android:id="@+id/bottom_bar"
             layout="@layout/voip_call_extra_actions"
diff --git a/app/src/main/res/layout/voip_call_main_actions.xml b/app/src/main/res/layout/voip_call_main_actions.xml
index f55c5bd0d..a8a12dd63 100644
--- a/app/src/main/res/layout/voip_call_main_actions.xml
+++ b/app/src/main/res/layout/voip_call_main_actions.xml
@@ -44,19 +44,20 @@
             android:paddingBottom="15dp"
             android:src="@drawable/hang_up"
             android:background="@drawable/shape_hang_up_button_background"
+            app:tint="@color/white"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintStart_toStartOf="parent" />
 
         <ImageView
             android:onClick="@{() -> viewModel.toggleVideo()}"
             android:id="@+id/toggle_video"
-            android:enabled="@{viewModel.isVideoEnabled}"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginEnd="16dp"
             android:padding="15dp"
-            android:src="@drawable/in_call_camera_button"
+            android:src="@{viewModel.isVideoEnabled() ? @drawable/camera_enabled : @drawable/camera_disabled, default=@drawable/camera_enabled}"
             android:background="@drawable/in_call_button_background"
+            app:tint="@color/white"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toStartOf="@id/toggle_mute_mic" />
 
@@ -74,6 +75,7 @@
             app:layout_constraintEnd_toStartOf="@id/change_audio_output" />
 
         <ImageView
+            android:onClick="@{() -> viewModel.changeAudioOutputDevice()}"
             android:id="@+id/change_audio_output"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
diff --git a/app/src/main/res/layout/voip_incoming_call_bottom_bar.xml b/app/src/main/res/layout/voip_incoming_call_bottom_bar.xml
index 7d05dcc22..2cd214b08 100644
--- a/app/src/main/res/layout/voip_incoming_call_bottom_bar.xml
+++ b/app/src/main/res/layout/voip_incoming_call_bottom_bar.xml
@@ -29,9 +29,25 @@
             android:paddingBottom="15dp"
             android:src="@drawable/hang_up"
             android:background="@drawable/shape_hang_up_button_background"
+            app:tint="@color/white"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintStart_toStartOf="parent" />
 
+        <ImageView
+            android:onClick="@{() -> viewModel.answer()}"
+            android:id="@+id/answer_call"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_marginEnd="30dp"
+            android:padding="15dp"
+            android:src="@drawable/calls"
+            android:background="@drawable/shape_answer_button_background"
+            app:tint="@color/white"
+            app:layout_constraintDimensionRatio="1:1"
+            app:layout_constraintTop_toTopOf="@id/hang_up"
+            app:layout_constraintBottom_toBottomOf="@id/hang_up"
+            app:layout_constraintEnd_toEndOf="parent" />
+
     </androidx.constraintlayout.widget.ConstraintLayout>
 
 </layout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/voip_outgoing_call_fragment.xml b/app/src/main/res/layout/voip_outgoing_call_fragment.xml
index 960bb7658..ac999da73 100644
--- a/app/src/main/res/layout/voip_outgoing_call_fragment.xml
+++ b/app/src/main/res/layout/voip_outgoing_call_fragment.xml
@@ -40,13 +40,14 @@
             app:layout_constraintTop_toTopOf="parent"/>
 
         <ImageView
+            android:onClick="@{() -> viewModel.switchCamera()}"
             android:id="@+id/switch_camera"
             android:layout_width="24dp"
             android:layout_height="24dp"
             android:layout_marginEnd="10dp"
             android:adjustViewBounds="true"
             android:src="@drawable/switch_camera"
-            android:enabled="@{viewModel.isVideoEnabled()}"
+            android:visibility="@{viewModel.isVideoEnabled() ? View.VISIBLE : View.GONE}"
             app:layout_constraintTop_toTopOf="@id/call_direction_label"
             app:layout_constraintBottom_toBottomOf="@id/call_direction_label"
             app:layout_constraintEnd_toEndOf="parent"
diff --git a/app/src/main/res/values/attrs.xml b/app/src/main/res/values/attrs.xml
new file mode 100644
index 000000000..4a83f3dea
--- /dev/null
+++ b/app/src/main/res/values/attrs.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <declare-styleable name="RoundCornersTextureView">
+        <attr name="alignTopRight" format="boolean" />
+        <attr name="displayMode" format="enum">
+            <enum name="black_bars" value="0"/>
+            <enum name="occupy_all_space" value="1"/>
+            <enum name="hybrid" value="2"/>
+        </attr>
+        <attr name="radius" format="float" />
+    </declare-styleable>
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/dimen.xml b/app/src/main/res/values/dimen.xml
index 5d74d6bcd..a76a5d803 100644
--- a/app/src/main/res/values/dimen.xml
+++ b/app/src/main/res/values/dimen.xml
@@ -14,6 +14,7 @@
     <dimen name="in_call_main_actions_menu_height">116dp</dimen>
     <dimen name="in_call_extra_actions_menu_height">237dp</dimen>
     <dimen name="in_call_all_actions_menu_height">353dp</dimen> <!-- sum of above two -->
+    <dimen name="in_call_round_corners_texture_view_radius">20dp</dimen>
 
     <dimen name="toast_max_width">360dp</dimen>
 </resources>
\ No newline at end of file