diff --git a/src/main/java/ecorp/easy/installer/controllers/MainWindowController.java b/src/main/java/ecorp/easy/installer/controllers/MainWindowController.java
index e068bd8462a8591dc5c98f3e5980201e29a3ba2a..0417dc51e59765be27eff8c06fd01079a0fd3c7d 100644
--- a/src/main/java/ecorp/easy/installer/controllers/MainWindowController.java
+++ b/src/main/java/ecorp/easy/installer/controllers/MainWindowController.java
@@ -21,10 +21,12 @@ import ecorp.easy.installer.controllers.subcontrollers.AbstractSubController;
 import ecorp.easy.installer.EasyInstaller;
 import ecorp.easy.installer.models.Device;
 import ecorp.easy.installer.threads.ThreadFactory;
+import ecorp.easy.installer.utils.UiUtils;
 
 import java.io.IOException;
 import java.net.URL;
 import java.util.ResourceBundle;
+import javafx.animation.FadeTransition;
 
 import javafx.fxml.Initializable;
 import javafx.application.Platform;
@@ -36,9 +38,11 @@ import javafx.scene.control.Label;
 import javafx.scene.input.MouseEvent;
 import javafx.fxml.FXML;
 import javafx.fxml.FXMLLoader;
+import javafx.scene.Node;
 import javafx.scene.layout.AnchorPane;
 import javafx.scene.layout.Pane;
 import javafx.scene.control.Button;
+import javafx.util.Duration;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 /**
@@ -159,56 +163,45 @@ public class MainWindowController implements Initializable {
         logger.info("loadSubScene("+currentSubRootId+")");
         
         if(currentSubRootId == null || currentSubRootId.isEmpty()){
-            currentSubRootId =loadSubUI("1-beforeYouBegin.fxml");
-            titleLabel.setText(i18n.getString("before_mTitle"));
+            
+            currentSubRootId =loadSubUI("1-beforeYouBegin.fxml", "before_mTitle").getId();
         }else{
             switch(currentSubRootId){
                 case "beforeYouBeginRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId = loadSubUI("2-connectDevice.fxml");
-                    this.titleLabel.setText(i18n.getString("connect_mTitle"));
+                    changeView(currentSubRootId, "2-connectDevice.fxml", "connect_mTitle");
                     break;
                 case "connectDeviceRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId = loadSubUI("3-enableADB.fxml");
-                    this.titleLabel.setText(i18n.getString("devMode_mTitle"));
+                    changeView(currentSubRootId, "3-enableADB.fxml", "devMode_mTitle");
                     break;
                 case "enableDevMode":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId = loadSubUI("4-deviceDetected.fxml");
-                    this.titleLabel.setText(i18n.getString("detect_mTitle"));
+                    changeView(currentSubRootId, "4-deviceDetected.fxml", "detect_mTitle");
                     disableNextButton(true);
                     break;
                 case "deviceDetectedRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId = loadSubUI("5-downloadSrc.fxml");
-                    this.titleLabel.setText(i18n.getString("download_mTitle"));
+                    changeView(currentSubRootId, "5-downloadSrc.fxml", "download_mTitle");
                     disableNextButton(true);
                     break;
                 case "downloadSceneRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId = loadSubUI("6-flashScene.fxml");
-                    this.titleLabel.setText(i18n.getString("installationTitle"));
+                    changeView(currentSubRootId, "6-flashScene.fxml", "installationTitle");
                     break;
                 case "flashSceneRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId= loadSubUI("7-flashResult.fxml");
+                    changeView(currentSubRootId, "7-flashResult.fxml", "installationTitle");
                     break;
                 case "flashResultRoot":
-                    removeNodeFromRoot(currentSubRootId);
+                    final String fxmlFileName;
+                    final String nextViewTitle;
                     if( isFlashed ){
-                        currentSubRootId=loadSubUI("8-congrats.fxml");
-                        this.titleLabel.setText(i18n.getString("congrats_mTitle"));
+                        fxmlFileName = "8-congrats.fxml";
+                        nextViewTitle ="congrats_mTitle";
                     }
                     else{
-                        currentSubRootId=loadSubUI("9-feedback.fxml");
-                        this.titleLabel.setText(i18n.getString("feedback_mTitle"));      
+                        fxmlFileName = "9-feedback.fxml";
+                        nextViewTitle ="feedback_mTitle";    
                     }
+                    changeView(currentSubRootId, fxmlFileName, nextViewTitle);
                     break;
                 case "congratsRoot":
-                    removeNodeFromRoot(currentSubRootId);
-                    currentSubRootId=loadSubUI("9-feedback.fxml");
-                    this.titleLabel.setText(i18n.getString("feedback_mTitle"));
+                    changeView(currentSubRootId, "9-feedback.fxml", "feedback_mTitle");
                     break;
                 case "feedbackRoot":
                     Platform.exit();
@@ -221,9 +214,7 @@ public class MainWindowController implements Initializable {
     }
     
     public void retryToFlash(){
-        removeNodeFromRoot(currentSubRootId);
-        currentSubRootId = loadSubUI("6-flashScene.fxml");
-        this.titleLabel.setText(i18n.getString("installationTitle"));
+        changeView(currentSubRootId, "6-flashScene.fxml", "installationTitle");
     }
     
     /**
@@ -235,15 +226,45 @@ public class MainWindowController implements Initializable {
         this.device = device;
     }
     
+    /**
+     * Used to remove currentView's root node from scene
+     * Required for return to flashScene after accountUI view
+     * @param rootId 
+     */
+    public void removeNodeFromRoot(final String rootId) {
+        root.getChildren().removeIf( n -> n.getId().equals(rootId));
+    }
     
     /**
-     * Remove a node from the root
-     * @param nodeId fx:id of the node
-     * @return true if element removed
+     * Close previous view after a fadeOut, and open new view
+     * @param previousNodeId
+     * @param fxmlName
+     * @param viewTitle 
      */
-    public boolean removeNodeFromRoot(String nodeId){
-        return root.getChildren().removeIf( n -> n.getId().equals(nodeId));
+    public void changeView(final String previousNodeId, final String fxmlName, final String viewTitle){
+        Node elementNode = null;
+        //get current subroot
+        for(Node node : root.getChildren() ){
+            if( node.getId().equals(previousNodeId) ){
+                elementNode = node;
+                break;
+            }
+        }
+        if(elementNode == null) return ;
+        //apply transition
+        final FadeTransition fadeOutTransition = UiUtils.buildFadeTransition(elementNode, true);
+        
+        fadeOutTransition.setOnFinished(e -> { 
+            removeNodeFromRoot(previousNodeId);
+            final Node subRoot =  loadSubUI(fxmlName, viewTitle);
+            currentSubRootId= subRoot.getId();
+            
+            subRoot.setOpacity(0.0);
+            UiUtils.buildFadeTransition(subRoot,false).play();
+        });
+        fadeOutTransition.play();
     }
+    
  
     /**
      * Load UI from FXML file
@@ -267,13 +288,17 @@ public class MainWindowController implements Initializable {
     /**
      * Load the subScene from FXML and return the controller
      * @param fxmlName fxml file name
+     * @param viewTitle the title for the new View
      * @return subRoot.
      */
-    public String loadSubUI(String fxmlName){
+    public Node loadSubUI(final String fxmlName, final String viewTitle){
+        logger.debug("view title: "+viewTitle);
+        if(viewTitle != null) titleLabel.setText(i18n.getString(viewTitle));
         FXMLLoader loader = loadFXML(fxmlName);
         Pane subRoot = (Pane) loader.getRoot();
         root.getChildren().add(0, subRoot); //adding this element as first subNode, let other element like button to still be clickable on small screen
-        return subRoot.getId();
+        
+        return subRoot;
     }
     
     /**
@@ -339,4 +364,5 @@ public class MainWindowController implements Initializable {
     public Device getDevice() {
         return device;
     }
+
 }
diff --git a/src/main/java/ecorp/easy/installer/controllers/subcontrollers/EnableADBController.java b/src/main/java/ecorp/easy/installer/controllers/subcontrollers/EnableADBController.java
index 44aab4a891b70e0f643867ce204db158bc88f93e..3ed591804bb9fda7d0d390aa16546b6dbd992a18 100644
--- a/src/main/java/ecorp/easy/installer/controllers/subcontrollers/EnableADBController.java
+++ b/src/main/java/ecorp/easy/installer/controllers/subcontrollers/EnableADBController.java
@@ -16,13 +16,19 @@
  */
 package ecorp.easy.installer.controllers.subcontrollers;
 
+import ecorp.easy.installer.utils.UiUtils;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.ResourceBundle;
+import javafx.animation.FadeTransition;
+import javafx.event.ActionEvent;
+import javafx.event.EventHandler;
 import javafx.fxml.FXML;
 import javafx.scene.control.Label;
 import javafx.scene.image.Image;
 import javafx.scene.image.ImageView;
+import javafx.scene.layout.HBox;
+import javafx.util.Duration;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -37,7 +43,7 @@ public class EnableADBController extends AbstractSubSteppedController  {
     @FXML private Label firstSubStep;
     @FXML private Label secondSubStep;
     @FXML private Label thirdSubStep;
-    
+    @FXML private HBox instructionsContainer;
     @FXML private ImageView enableADBImg;
     
     private ArrayList<Label> instructions; //Used to iterate over instructions
@@ -69,38 +75,48 @@ public class EnableADBController extends AbstractSubSteppedController  {
 
     @Override
     protected void onNextButtonClicked() {
-        //Instruction for enabling Developer mode
-
-        deemphasizeLabel(instructions.get(currentEmphasedLbl));
-        
-        if(currentEmphasedLbl == instructions.size()-1)
-            currentEmphasedLbl = 0;
-        else{
-            currentEmphasedLbl++;
-        }
-        
-        emphasizeLabel(instructions.get(currentEmphasedLbl));
-        updateImage();
-        
         switch (currentSubStepId) {
             case 2:
-                //Update UI to show instruction to enable ADB Debuging
-                parentController.setViewTitle("debugADB_mTitle");
-                firstSubStep.setText(i18n.getString("debugADB_instr_settings"));
-                secondSubStep.setText(i18n.getString("debugADB_instr_search"));
-                thirdSubStep.setText(i18n.getString("debugADB_instr_androidDebug"));
+                UiUtils.playFadeAnimation(instructionsContainer, e->{
+                    parentController.setViewTitle("debugADB_mTitle");
+                    firstSubStep.setText(i18n.getString("debugADB_instr_settings"));
+                    secondSubStep.setText(i18n.getString("debugADB_instr_search"));
+                    thirdSubStep.setText(i18n.getString("debugADB_instr_androidDebug"));
+                    changeHighlightedInstruction();
+                }, e->{});
                 break;
             case 5:
-                parentController.setViewTitle("enableMTP_mTitle");
-                firstSubStep.setText(i18n.getString("enableMTP_instr_settings"));
-                secondSubStep.setText(i18n.getString("enableMTP_instr_scrollToUSBConfig"));
-                thirdSubStep.setText(i18n.getString("enableMTP_instr_selectMTP"));
+                //play transition
+                UiUtils.playFadeAnimation(instructionsContainer, e->{
+                    parentController.setViewTitle("enableMTP_mTitle");
+                    firstSubStep.setText(i18n.getString("enableMTP_instr_settings"));
+                    secondSubStep.setText(i18n.getString("enableMTP_instr_scrollToUSBConfig"));
+                    thirdSubStep.setText(i18n.getString("enableMTP_instr_selectMTP"));
+                    changeHighlightedInstruction();
+                }, e->{});
+                
                 break;
             case 7:
                 parentController.resetNextButtonEventHandler();
+                changeHighlightedInstruction();
                 break;
             default:
+                changeHighlightedInstruction();
                 break;
         }
+    }        
+      
+
+    
+    private void changeHighlightedInstruction(){
+        deemphasizeLabel(instructions.get(currentEmphasedLbl));
+        
+        if(currentEmphasedLbl == instructions.size()-1)
+            currentEmphasedLbl = 0;
+        else{
+            currentEmphasedLbl++;
+        }
+        emphasizeLabel(instructions.get(currentEmphasedLbl));
+        updateImage();
     }
 }
diff --git a/src/main/java/ecorp/easy/installer/controllers/subcontrollers/FlashSceneController.java b/src/main/java/ecorp/easy/installer/controllers/subcontrollers/FlashSceneController.java
index 5bc16ab2a1e82579ff29bf4b778a5bcf0de10ed5..14db165eca4169037faabeb7e02bdf2f3a77aeb3 100644
--- a/src/main/java/ecorp/easy/installer/controllers/subcontrollers/FlashSceneController.java
+++ b/src/main/java/ecorp/easy/installer/controllers/subcontrollers/FlashSceneController.java
@@ -28,14 +28,17 @@ import ecorp.easy.installer.threads.FlashThread;
 import ecorp.easy.installer.tasks.TimerTask;
 import ecorp.easy.installer.tasks.UploadToEcloudTask;
 import ecorp.easy.installer.utils.IFlashHandler;
+import ecorp.easy.installer.utils.UiUtils;
 
 import java.net.URL;
 import java.util.List;
 import java.util.Locale;
 import java.util.ResourceBundle;
+import javafx.animation.FadeTransition;
 import javafx.collections.ObservableList;
 import javafx.fxml.FXML;
 import javafx.geometry.Pos;
+import javafx.scene.Node;
 import javafx.scene.control.Button;
 import javafx.scene.control.Label;
 import javafx.scene.control.ProgressBar;
@@ -46,6 +49,7 @@ import javafx.scene.input.MouseEvent;
 import javafx.scene.layout.HBox;
 import javafx.scene.layout.VBox;
 import javafx.scene.text.TextFlow;
+import javafx.util.Duration;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -63,7 +67,8 @@ public class FlashSceneController extends AbstractSubSteppedController implement
     @FXML Label stepTitleLabel;
     @FXML ImageView instructionImage;
     @FXML ImageView stepTitleIcon;
-
+    @FXML HBox instructionsContainer;
+    
     // progress bar's node of global Flash's process :
     @FXML HBox globalProgressIndicator;
     private FlashGlobalProgressManager globalProgressMgr;
@@ -88,14 +93,9 @@ public class FlashSceneController extends AbstractSubSteppedController implement
     public void initialize(URL location, ResourceBundle resources) {
         super.initialize(location, resources);
         logger.debug("Initialize FlashSceneController.java");
-
-        sendLogBtn.managedProperty().bind(sendLogBtn.visibleProperty());
-        loadStepProgressIndicator.managedProperty().bind(loadStepProgressIndicator.visibleProperty());
-        logScrollPane.managedProperty().bind(logScrollPane.visibleProperty());
         logFlow.heightProperty().addListener(observable -> logScrollPane.setVvalue(1.0));   
-        
-        logScrollPane.setVisible(false);
-        sendLogBtn.setVisible(false);
+        UiUtils.hideNode(logScrollPane);
+        UiUtils.hideNode(sendLogBtn);
     }
     
     @Override
@@ -110,7 +110,7 @@ public class FlashSceneController extends AbstractSubSteppedController implement
                                                              .setLanguage("EN")
                                                              .setVariant(DeviceHelper.getDeviceInternalcode(parentController.getDevice().getDevice()))
                                                              .build());
-        pauseLock = new Object();
+        pauseLock = new Object(); //This is object used to unpause a thread
 
         thread = parentController.getThreadFactory().buildFlashThread(this, pauseLock);
         if(thread!= null){
@@ -139,7 +139,6 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         label.minWidthProperty().bind(instructionsFlow.widthProperty()); //avoid to display two instruction on the same line
         label.maxWidthProperty().bind(instructionsFlow.widthProperty()); //Set max Width to its parent width
         instructionsFlow.getChildren().add(label);
-
     }
     
     /**
@@ -149,8 +148,6 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         globalProgressMgr.updateProgression();
     }
     
-
-    
     /**
      * UI changes at beginning of a new step
      * @TODO: move part of code relative to 'action' step to 'setActionStepUI()', and 'load' type to 'setLoadStepUI()'
@@ -161,7 +158,8 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         logger.info("onStepStart()");
         logger.debug("    DataBundle = {}", db.toString());
         if(db == null)return;
-        
+
+        //close the timer of a loadStepType 
         if(timer != null){
             timer.cancel();
             timer = null;
@@ -169,38 +167,24 @@ public class FlashSceneController extends AbstractSubSteppedController implement
 
         //Update the progressBar of the global process
         updateProgressBar();
-              
-        //update instructions
-        instructionsKey = db.getList("stepInstructions", "String");
-        if(instructionsKey != null){
-            instructionsFlow.getChildren().clear();
-            instructionsKey.forEach((instruction) -> {
-                addInstructionToDisplay(instruction);
-            });
-            
-            //Update instruction image
-            String instructionImgName = instructionsKey.get(0);
-            try{
-                this.instructionImage.setImage(new Image(getClass().getResourceAsStream("/images/"+instructionsImagesBundle.getString(instructionImgName))));
-            }catch (Exception e) {
-                logger.warn("onStepStart(), image key = {}, error = {}", instructionImgName, e.toString());
-                this.instructionImage.setImage(null);
-            }
-        }
-        
-        //Update instruction title
-        String title = db.getString("stepTitle");
-        if(title != null){
-            stepTitleLabel.setText(i18n.getString(title));
-        }
 
+        //Update instruction title
+        final String title = db.getString("stepTitle");
+        logger.debug("Title: "+title);
+        
         //Get Type of step ("action" or "load")
         switch(db.getString("stepType")){
             case AppConstants.USER_ACTION_KEY:
-                onActionStepType(db);
+                instructionsContainer.setOpacity(0.0);
+                updateInstructions(title, db.getList("stepInstructions", "String") );
+                onActionStepType(db); 
+                UiUtils.buildFadeTransition(instructionsContainer, false).play();
                 break;
             case AppConstants.LOAD_KEY:
+                instructionsContainer.setOpacity(0.0);
+                updateInstructions(title, db.getList("stepInstructions", "String"));
                 onLoadStepType(db);
+                UiUtils.buildFadeTransition(instructionsContainer, false).play();
                 break;
             case AppConstants.ASK_ACCOUNT_KEY:
                 displaySpecificView("6-2-eAccount.fxml");
@@ -212,29 +196,73 @@ public class FlashSceneController extends AbstractSubSteppedController implement
                 logger.warn("Try to load invalid step's type");
                 break;
         }
-
     }
 
+    /**
+     * Update text and images instructions
+     * @param instructionsKey 
+     */
+    private void updateInstructions(final String title, final List<String> instructionsKey){
+        if(title != null){
+            stepTitleLabel.setText(i18n.getString(title));
+        }        
+
+        //update instructions
+        if(instructionsKey == null || instructionsKey.isEmpty()) return; 
+        this.instructionsKey = instructionsKey;
+        
+        //Remove precedent instruction
+        instructionsFlow.getChildren().clear();
+        
+        //Add new instructions
+        instructionsKey.forEach((instruction) -> {
+            addInstructionToDisplay(instruction);
+        });
+
+        //Update instruction image
+        String instructionImgName = instructionsKey.get(0);
+        try{
+            this.instructionImage.setImage(new Image(getClass().getResourceAsStream("/images/"+instructionsImagesBundle.getString(instructionImgName))));
+        }catch (Exception e) {
+            logger.warn("onStepStart(), image key = {}, error = {}", instructionImgName, e.toString());
+            this.instructionImage.setImage(null);
+        }
+    }
+    
+    
+    
+    
     /**
      * Display the specific interface for
      * Note: This could be replace by a call to parentController.loadSubUI("6-2-eAccount.fxml")
      * but how to reset current ui to this one after ?
      */
-    private void displaySpecificView(String fxmlName){
+    private void displaySpecificView(final String fxmlName){
         //Masque previous UI
-        //@TODO it's better to apply to each children
-        flashSceneRoot.setVisible(false);
-        flashSceneRoot.setManaged(false);
+        UiUtils.hideNode(flashSceneRoot);
         //Affiche the new One
-        final String tempRootId = parentController.loadSubUI(fxmlName);
+        final Node tempRoot = parentController.loadSubUI(fxmlName, null);
+        
+        //play fade out animation 
+        tempRoot.setOpacity(0.0);
+        UiUtils.buildFadeTransition(tempRoot,false).play();
+        
+        //Define what happened when user click on continue on this specific view
+        final String tempRootId = tempRoot.getId(); 
         parentController.setNextButtonOnClickListener(( MouseEvent event) -> {
-            parentController.resetNextButtonEventHandler();
-            parentController.removeNodeFromRoot(tempRootId);
-            parentController.showCurrentSubRoot();
-            parentController.setNextButtonVisible(false);
-            synchronized (pauseLock) {
-                pauseLock.notify();
-            }
+            //this is where I have to put fade in transition
+            final FadeTransition fadeInAnimation = UiUtils.buildFadeTransition(tempRoot,true);
+            fadeInAnimation.setOnFinished(t->{
+                parentController.resetNextButtonEventHandler();
+                parentController.removeNodeFromRoot(tempRootId);
+                parentController.showCurrentSubRoot();
+                parentController.setNextButtonVisible(false);
+                synchronized (pauseLock) {
+                    pauseLock.notify();
+                }
+            });
+            
+            fadeInAnimation.play();
         });
     }
 
@@ -244,20 +272,20 @@ public class FlashSceneController extends AbstractSubSteppedController implement
      */
     private void onLoadStepType(DataBundle db){
         logger.info("onLoadStepType()");
-        instructionsVBox.setAlignment(Pos.CENTER);
+        UiUtils.hideNode(instructionsFlow); //put it invisible instead ?
+        instructionsVBox.setAlignment(Pos.TOP_CENTER);
         parentController.setNextButtonVisible(false);
         int averageTime = db.getInt("averageTime");
         logger.debug("averageTime = {} ", averageTime);
         if(averageTime > -1){ //Or > 0 ?
             timer = new TimerTask(averageTime, this);
             loadStepProgressIndicator.setProgress(0.0); //Reset to prevent showing last value
-            loadStepProgressIndicator.setVisible(true);
+            UiUtils.showNode(loadStepProgressIndicator);
             Thread timerThread = new Thread(timer);
             timerThread.setDaemon(true);
             timerThread.start();
         }
         this.stepTitleIcon.setImage(null);
-        this.instructionsFlow.setVisible(false); //put it invisible instead ?
     }
     
     /**
@@ -276,8 +304,8 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         setNextButtonOnClickListener();
 
         //Hide progress Indicator
-        loadStepProgressIndicator.setVisible(false);
-        instructionsFlow.setVisible(true);
+        UiUtils.hideNode(loadStepProgressIndicator);
+        UiUtils.showNode(instructionsFlow);
 
         //Set Title Icon if defined
         String titleIconName = db.getString("titleIconName");
@@ -301,9 +329,8 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         
         logger.debug("errorMsgKey = {}", errorMsgKey);
 
-        instructionsFlow.setManaged(false);
-        instructionsFlow.setVisible(false);
-        sendLogBtn.setVisible(true);
+        UiUtils.hideNode(instructionsFlow);
+        UiUtils.showNode(sendLogBtn);
         
         Button tryAgainBtn = new Button(i18n.getString("all_lbl_tryAgain"));
         tryAgainBtn.setOnMouseClicked(( MouseEvent event) -> {
@@ -331,7 +358,6 @@ public class FlashSceneController extends AbstractSubSteppedController implement
     @Override
     public void onFlashStop(DataBundle db) {
         logger.info("onFlashStop()");
-        //flashStepTitleLabel.setText("Stopped");
         if(timer != null){
             timer.cancel();
             timer = null;
@@ -368,18 +394,15 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         ch.qos.logback.classic.Logger rootLogger = (ch.qos.logback.classic.Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
         GUIAppender appender = (GUIAppender) rootLogger.getAppender("GUI");
 
-
-        String text = showHideLogBtn.getText();
+        final String text = showHideLogBtn.getText();
         if(text.equals(">")){
             showHideLogBtn.setText("V");
-            logScrollPane.setVisible(false);
-
+            UiUtils.hideNode(logScrollPane);
             logFlow.getChildren().clear();
             appender.setContainer(null);
         }else{
             showHideLogBtn.setText(">");
-            logScrollPane.setVisible(true);
-
+            UiUtils.showNode(logScrollPane);
             logFlow.getChildren().addAll(appender.getLogsList());
             appender.setContainer(logFlow);
         }
@@ -439,7 +462,6 @@ public class FlashSceneController extends AbstractSubSteppedController implement
         final ObservableList children = instructionsFlow.getChildren();
         final int instructionsNumber = children.size();
 
-
         /*
         check that there is more than 1 instruction. (children's size is > 1).
         Then if it's not the case, just return.
diff --git a/src/main/java/ecorp/easy/installer/utils/UiUtils.java b/src/main/java/ecorp/easy/installer/utils/UiUtils.java
new file mode 100644
index 0000000000000000000000000000000000000000..867a03eb599e630e1df6b481d69f92a0f098d9dd
--- /dev/null
+++ b/src/main/java/ecorp/easy/installer/utils/UiUtils.java
@@ -0,0 +1,79 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package ecorp.easy.installer.utils;
+
+import javafx.animation.FadeTransition;
+import javafx.event.ActionEvent;
+import javafx.event.EventHandler;
+import javafx.scene.Node;
+import javafx.util.Duration;
+
+/**
+ *
+ * @author vincent
+ */
+public abstract class UiUtils {
+    
+    
+    /**
+     * Makes Node not managed and not visible
+     * It is used to hide an element on the view
+     * @param node 
+     */
+    public final static void hideNode(final Node node){
+        node.setManaged(false);
+        node.setVisible(false);
+    }
+    
+    /**
+     * Makes a node visible and managed
+     * It is used to display an element which has been hidden
+     * @param node 
+     */
+    public final static void showNode(final Node node){
+        node.setManaged(true);
+        node.setVisible(true);
+    }
+    
+    /**
+     * Build a Fade in or Fade out animation for a specified Node
+     * @param node The node that will fade
+     * @param isFadeIn true if it's a fade in animation. False if it's a fade out animation.
+     * @return FadeTransition the animation
+     */
+    public final static FadeTransition buildFadeTransition(final Node node, boolean isFadeIn){
+        final FadeTransition transition = new FadeTransition(Duration.millis(300), node);
+        transition.setFromValue(isFadeIn ? 1.0 : 0.0);
+        transition.setToValue(isFadeIn ? 0.0 : 1.0);
+
+        return transition;
+    }
+    
+    
+    /**
+     * could have a suffix: on the same node!
+     * Play fade in animation then fade out animation.
+     * @param node The node whichs will fade in/fadeout. it is used for fade in & fade out!
+     * @param handler1 Handler applied at the end of fade in transition
+     * @param handler2 handler applied at the end of fade out transition
+     */
+    public final static void playFadeAnimation(final Node node, final EventHandler<ActionEvent> handler1, final EventHandler<ActionEvent>handler2){
+        FadeTransition transition = new FadeTransition(Duration.millis(300), node);
+        transition.setFromValue(1.0);
+        transition.setToValue(0.0);
+        transition.setAutoReverse(true);
+        transition.play();
+        
+        transition.setOnFinished(e -> {
+            handler1.handle(e);
+            
+            transition.setRate(-1.0);
+            transition.play();
+            transition.setOnFinished(handler2); 
+        });
+    }
+    
+}
diff --git a/src/main/resources/fxml/3-enableADB.fxml b/src/main/resources/fxml/3-enableADB.fxml
index a362fb2004d616740a800e7899d8084abf615a36..d3bf8bdc7f3c8eee4c304f21072612158d5aae32 100644
--- a/src/main/resources/fxml/3-enableADB.fxml
+++ b/src/main/resources/fxml/3-enableADB.fxml
@@ -33,9 +33,9 @@
             fx:controller="ecorp.easy.installer.controllers.subcontrollers.EnableADBController">
    <children>
       <Label fx:id="pleaseFollowThisStepsLbl"  text="%devMode_lbl" wrapText="true"/>
-      <HBox spacing="20" alignment="CENTER" >
+      <HBox fx:id="instructionsContainer" spacing="20" alignment="CENTER" >
           <children>
-                <VBox fx:id="instructionsContainer" alignment="CENTER" maxHeight="433.0" >
+                <VBox alignment="CENTER" maxHeight="433.0" >
                     <children>
                         <HBox VBox.vgrow="ALWAYS" alignment="CENTER_LEFT" spacing="10">
                             <children >
diff --git a/src/main/resources/fxml/6-flashScene.fxml b/src/main/resources/fxml/6-flashScene.fxml
index 4bf31d20a417d42431306acaf9b1cf0fd834215b..b20a53eb3210bb91db4092e5194386c3fd2a6f45 100644
--- a/src/main/resources/fxml/6-flashScene.fxml
+++ b/src/main/resources/fxml/6-flashScene.fxml
@@ -34,7 +34,7 @@
     fx:controller="ecorp.easy.installer.controllers.subcontrollers.FlashSceneController">
     <children>
         <HBox fx:id="globalProgressIndicator" spacing="2" minHeight="50.0" alignment="CENTER"/>
-        <HBox spacing="20" alignment="TOP_CENTER" VBox.vgrow="ALWAYS" maxWidth="1000.0">
+        <HBox fx:id="instructionsContainer" spacing="20" alignment="TOP_CENTER" VBox.vgrow="ALWAYS" maxWidth="1000.0">
             <children>
                 <ImageView fx:id="stepTitleIcon" />
                 <VBox fx:id="instructionsVBox" spacing="15.0" HBox.hgrow="ALWAYS">