diff --git a/app/build.gradle b/app/build.gradle
index c03aace7937974b50e747735796a582b698ea104..c03f615f09c53617f3463457fbead1168ed132c7 100755
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -86,4 +86,6 @@ dependencies {
 
     //Theme Engine
     implementation 'com.jaredrummler:cyanea:1.0.2'
+
+    implementation 'foundation.e:elib:0.0.1-alpha11'
 }
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 85ad8f3a82384bb8c6e72c1a08123beecc884173..a907548a7e0cf712cf77b07c0ecb136eef76c07a 100755
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -15,7 +15,7 @@
         android:supportsRtl="true"
         android:requestLegacyExternalStorage="true"
         android:usesCleartextTraffic="true"
-        android:theme="@style/Theme.Cyanea.Light.DarkActionBar">
+        android:theme="@style/AppTheme">
 
         <activity
             android:name=".MainActivity"
diff --git a/app/src/main/java/com/gsnathan/pdfviewer/AboutActivity.java b/app/src/main/java/com/gsnathan/pdfviewer/AboutActivity.java
index a2c1c9e11f04d998569fb5f038a4dfbbd31325d4..5a0d451c2919c3a076d3e5a33d091d2ce5a1babd 100755
--- a/app/src/main/java/com/gsnathan/pdfviewer/AboutActivity.java
+++ b/app/src/main/java/com/gsnathan/pdfviewer/AboutActivity.java
@@ -34,15 +34,15 @@ import android.widget.Toast;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.fragment.app.DialogFragment;
 
 import com.franmontiel.attributionpresenter.AttributionPresenter;
 import com.franmontiel.attributionpresenter.entities.Attribution;
 import com.franmontiel.attributionpresenter.entities.License;
 import com.gsnathan.pdfviewer.databinding.ActivityAboutBinding;
-import com.jaredrummler.cyanea.app.CyaneaAppCompatActivity;
 
-public class AboutActivity extends CyaneaAppCompatActivity {
+public class AboutActivity extends AppCompatActivity {
 
     private ActivityAboutBinding viewBinding;
     private final String APP_VERSION_RELEASE = "Version " + Utils.getAppVersion();   //contains Version + the version number
@@ -80,7 +80,7 @@ public class AboutActivity extends CyaneaAppCompatActivity {
     }
 
     public void showLicense(View v) {
-        startActivity(Utils.linkIntent("https://github.com/JavaCafe01/PdfViewer/blob/master/LICENSE"));
+        startActivity(Utils.linkIntent(getString(R.string.e_pdfviewer_license)));
     }
 
     public void showLibraries(View v) {
@@ -157,11 +157,11 @@ public class AboutActivity extends CyaneaAppCompatActivity {
     }
 
     public void navToGit(View v) {
-        startActivity(Utils.linkIntent("https://github.com/JavaCafe01"));
+        startActivity(Utils.linkIntent(getString(R.string.e_gitlab)));
     }
 
     public void navToSourceCode(View v) {
-        startActivity(Utils.linkIntent("https://github.com/JavaCafe01/PdfViewer"));
+        startActivity(Utils.linkIntent(getString(R.string.e_pdfviewer)));
     }
 
     @Override
diff --git a/app/src/main/java/com/gsnathan/pdfviewer/AppCompatPreferenceActivity.java b/app/src/main/java/com/gsnathan/pdfviewer/AppCompatPreferenceActivity.java
new file mode 100644
index 0000000000000000000000000000000000000000..c0be0f4fdbf25c5a51727b9fb7f8a395f44c5311
--- /dev/null
+++ b/app/src/main/java/com/gsnathan/pdfviewer/AppCompatPreferenceActivity.java
@@ -0,0 +1,122 @@
+/*
+   Copyright Murena SAS 2022
+   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 <https://www.gnu.org/licenses/>.
+*/
+package com.gsnathan.pdfviewer;
+
+import android.content.res.Configuration;
+import android.os.Bundle;
+import android.preference.PreferenceActivity;
+import android.view.MenuInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import androidx.annotation.LayoutRes;
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatDelegate;
+import androidx.appcompat.widget.Toolbar;
+
+public abstract class AppCompatPreferenceActivity extends PreferenceActivity {
+
+    private AppCompatDelegate mDelegate;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        getDelegate().installViewFactory();
+        getDelegate().onCreate(savedInstanceState);
+        super.onCreate(savedInstanceState);
+    }
+
+    @Override
+    protected void onPostCreate(Bundle savedInstanceState) {
+        super.onPostCreate(savedInstanceState);
+        getDelegate().onPostCreate(savedInstanceState);
+    }
+
+    public ActionBar getSupportActionBar() {
+        return getDelegate().getSupportActionBar();
+    }
+
+    public void setSupportActionBar(@Nullable Toolbar toolbar) {
+        getDelegate().setSupportActionBar(toolbar);
+    }
+
+    @Override
+    public MenuInflater getMenuInflater() {
+        return getDelegate().getMenuInflater();
+    }
+
+    @Override
+    public void setContentView(@LayoutRes int layoutResID) {
+        getDelegate().setContentView(layoutResID);
+    }
+
+    @Override
+    public void setContentView(View view) {
+        getDelegate().setContentView(view);
+    }
+
+    @Override
+    public void setContentView(View view, ViewGroup.LayoutParams params) {
+        getDelegate().setContentView(view, params);
+    }
+
+    @Override
+    public void addContentView(View view, ViewGroup.LayoutParams params) {
+        getDelegate().addContentView(view, params);
+    }
+
+    @Override
+    protected void onPostResume() {
+        super.onPostResume();
+        getDelegate().onPostResume();
+    }
+
+    @Override
+    protected void onTitleChanged(CharSequence title, int color) {
+        super.onTitleChanged(title, color);
+        getDelegate().setTitle(title);
+    }
+
+    @Override
+    public void onConfigurationChanged(Configuration newConfig) {
+        super.onConfigurationChanged(newConfig);
+        getDelegate().onConfigurationChanged(newConfig);
+    }
+
+    @Override
+    protected void onStop() {
+        super.onStop();
+        getDelegate().onStop();
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        getDelegate().onDestroy();
+    }
+
+    AppCompatDelegate getDelegate() {
+        if (mDelegate == null) {
+            mDelegate = AppCompatDelegate.create(this, null);
+        }
+        return mDelegate;
+    }
+
+    public void invalidateOptionsMenu() {
+        getDelegate().invalidateOptionsMenu();
+    }
+
+}
diff --git a/app/src/main/java/com/gsnathan/pdfviewer/MainActivity.java b/app/src/main/java/com/gsnathan/pdfviewer/MainActivity.java
index 8b62c55777714d1512165bfbe5581b283adb3a90..a589195629035e98bbb9c5655f5f287be8169810 100755
--- a/app/src/main/java/com/gsnathan/pdfviewer/MainActivity.java
+++ b/app/src/main/java/com/gsnathan/pdfviewer/MainActivity.java
@@ -55,6 +55,7 @@ import androidx.activity.result.contract.ActivityResultContracts.StartActivityFo
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.core.content.ContextCompat;
 import androidx.fragment.app.DialogFragment;
 
@@ -78,7 +79,7 @@ import java.io.IOException;
 
 import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 
-public class MainActivity extends CyaneaAppCompatActivity {
+public class MainActivity extends AppCompatActivity {
 
     private static final String TAG = "MainActivity";
 
@@ -133,8 +134,6 @@ public class MainActivity extends CyaneaAppCompatActivity {
         prefManager = PreferenceManager.getDefaultSharedPreferences(this);
 
         mgr = (PrintManager) getSystemService(PRINT_SERVICE);
-        onFirstInstall();
-        onFirstUpdate();
 
         if (savedInstanceState != null) {
             restoreInstanceState(savedInstanceState);
@@ -157,26 +156,6 @@ public class MainActivity extends CyaneaAppCompatActivity {
         viewBinding.bottomNavigation.setBackgroundColor(Cyanea.getInstance().getPrimary());
     }
 
-    private void onFirstInstall() {
-        boolean isFirstRun = prefManager.getBoolean("FIRSTINSTALL", true);
-        if (isFirstRun) {
-            startActivity(new Intent(this, MainIntroActivity.class));
-            SharedPreferences.Editor editor = prefManager.edit();
-            editor.putBoolean("FIRSTINSTALL", false);
-            editor.apply();
-        }
-    }
-
-    private void onFirstUpdate() {
-        boolean isFirstRun = prefManager.getBoolean(Utils.getAppVersion(), true);
-        if (isFirstRun) {
-            Utils.showLog(this);
-            SharedPreferences.Editor editor = prefManager.edit();
-            editor.putBoolean(Utils.getAppVersion(), false);
-            editor.apply();
-        }
-    }
-
     @Override
     protected void onSaveInstanceState(@NonNull Bundle outState) {
         outState.putParcelable("uri", uri);
diff --git a/app/src/main/java/com/gsnathan/pdfviewer/SettingsActivity.java b/app/src/main/java/com/gsnathan/pdfviewer/SettingsActivity.java
index 2a004c5b74f1b8417761e304dc4afa18578636db..8dc8722c395c5fc5d988f4776c1db1d519712c2a 100644
--- a/app/src/main/java/com/gsnathan/pdfviewer/SettingsActivity.java
+++ b/app/src/main/java/com/gsnathan/pdfviewer/SettingsActivity.java
@@ -23,7 +23,7 @@ import static android.content.pm.PackageManager.COMPONENT_ENABLED_STATE_ENABLED;
 import static android.content.pm.PackageManager.DONT_KILL_APP;
 import static android.util.TypedValue.COMPLEX_UNIT_DIP;
 
-public class SettingsActivity extends CyaneaPreferenceActivity {
+public class SettingsActivity extends AppCompatPreferenceActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
diff --git a/app/src/main/res/drawable/lock_icon.xml b/app/src/main/res/drawable/lock_icon.xml
index 94f568ff4b79149abf401100cd5671b1f62c6bf0..65a62a524473b17cdcbbc85bd99d7eba483c5c9e 100644
--- a/app/src/main/res/drawable/lock_icon.xml
+++ b/app/src/main/res/drawable/lock_icon.xml
@@ -5,6 +5,6 @@
     android:viewportWidth="24"
     android:viewportHeight="24">
     <path
-        android:fillColor="#399"
+        android:fillColor="@color/e_icon_color"
         android:pathData="M12,1A5,5 0 0,0 7,6V8H6A2,2 0 0,0 4,10V20A2,2 0 0,0 6,22H18A2,2 0 0,0 20,20V10A2,2 0 0,0 18,8H17V6A5,5 0 0,0 12,1M12,2.9C13.71,2.9 15.1,4.29 15.1,6V8H8.9V6C8.9,4.29 10.29,2.9 12,2.9M11,11H13V15H11V11M11,17H13V19H11V17Z" />
 </vector>
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_about.xml b/app/src/main/res/layout/activity_about.xml
index e20f285d26f0213c97b768edb571d8ea403b9982..de60180a838f55957757258fdca479a4f45ab545 100755
--- a/app/src/main/res/layout/activity_about.xml
+++ b/app/src/main/res/layout/activity_about.xml
@@ -84,7 +84,8 @@
                 android:padding="16sp"
                 android:text="@string/app_info"
                 android:fontFamily="@font/roboto_medium"
-                android:textSize="16sp" />
+                android:textSize="16sp"
+                android:textColor="@color/e_accent"/>
 
             <TextView
                 android:id="@+id/introView"
@@ -93,10 +94,12 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/replay_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/intro"
-                android:textSize="16sp" />
+                android:textSize="16sp"
+                android:visibility="gone"/>
 
             <TextView
                 android:id="@+id/changeView"
@@ -105,10 +108,12 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/log_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/appChangelog"
-                android:textSize="16sp" />
+                android:textSize="16sp"
+                android:visibility="gone"/>
 
             <TextView
                 android:id="@+id/licenseView"
@@ -117,6 +122,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/license_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/myLicense"
@@ -129,6 +135,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/privacy_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/privacy"
@@ -141,6 +148,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/code_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/code"
@@ -153,6 +161,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/lib_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/libs"
@@ -164,7 +173,8 @@
                 android:padding="16sp"
                 android:text="@string/author_info"
                 android:fontFamily="@font/roboto_medium"
-                android:textSize="16sp" />
+                android:textSize="16sp"
+                android:textColor="@color/e_accent"/>
 
             <TextView
                 android:id="@+id/emailView"
@@ -173,6 +183,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/email_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/email"
@@ -185,6 +196,7 @@
                 android:layout_height="wrap_content"
                 android:background="?attr/selectableItemBackground"
                 android:drawableStart="@drawable/github_icon"
+                android:drawableTint="@color/e_icon_color"
                 android:drawablePadding="16dp"
                 android:padding="16sp"
                 android:text="@string/git"
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 3a3a8c092c7c730d356180a270a0506dde7e367b..753d2cc9710b7def3e7c524136fc63c6488f5bb7 100755
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -52,8 +52,9 @@
         android:layout_height="wrap_content"
         android:layout_gravity="bottom"
         android:minHeight="?android:attr/actionBarSize"
-        app:itemIconTint="?menuIconColor"
-        app:itemTextColor="?menuIconColor"
+        android:backgroundTint="@color/e_action_bar"
+        app:itemIconTint="@color/bottom_navigation_selector"
+        app:itemTextColor="@color/bottom_navigation_selector"
         app:labelVisibilityMode="unlabeled"
         app:menu="@menu/fab_menu" />
 
diff --git a/app/src/main/res/menu/menu.xml b/app/src/main/res/menu/menu.xml
index 9005768f06fa6fe1a9ea79e58e752078f22867b9..06a40dc05f1de3a1fab533cc0f9deafe7afcace2 100755
--- a/app/src/main/res/menu/menu.xml
+++ b/app/src/main/res/menu/menu.xml
@@ -42,5 +42,6 @@
         android:id="@+id/theme"
         android:orderInCategory="1"
         android:title="@string/theme_picker"
-        app:showAsAction="never" />
+        app:showAsAction="never"
+        android:visible="false"/>
 </menu>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 32b3c5e4cd1be712765b5b8dae706256756e0c79..dfd912f3f455b7ece43180f288269a29d352f4f3 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -122,4 +122,8 @@
     <string name="dark_pdf">Dark theme for PDF</string>
     <string name="keep_screen_on">Keep the screen on</string>
     <string name="privacy_info">This app does not collect any data.\nThe following permissions are required to provide specific features in the app:\n- <b>Internet</b>: open PDFs through links\n- <b>Storage</b>: open files from storage, save PDFs opened through links</string>
+
+    <string name="e_gitlab" translatable="false">https://gitlab.e.foundation/</string>
+    <string name="e_pdfviewer" translatable="false">https://gitlab.e.foundation/e/os/pdfviewer/</string>
+    <string name="e_pdfviewer_license" translatable="false">https://gitlab.e.foundation/e/os/pdfviewer/-/blob/main/LICENSE</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
new file mode 100755
index 0000000000000000000000000000000000000000..bbbd876b37dc703ec2e20ed6c5aef170ecc3ffd0
--- /dev/null
+++ b/app/src/main/res/values/styles.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright Murena SAS 2022
+  ~ 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 <https://www.gnu.org/licenses/>.
+  -->
+<resources>
+   <style name="AppTheme" parent="Theme.AppCompat.DayNight">
+      <item name="colorPrimary">@color/e_accent</item>
+      <item name="colorAccent">@color/e_accent</item>
+      <item name="android:windowBackground">@color/e_background</item>
+      <item name="android:textColorPrimary">@color/e_primary_text_color</item>
+      <item name="android:textColorSecondary">@color/e_secondary_text_color</item>
+      <item name="android:navigationBarColor">@color/e_action_bar</item>
+      <item name="android:statusBarColor">@color/e_action_bar</item>
+      <item name="android:windowLightNavigationBar">@bool/isLight</item>
+      <item name="android:windowLightStatusBar">@bool/isLight</item>
+      <item name="android:itemBackground">@color/e_floating_background</item>
+      <item name="actionBarStyle">@style/ActionBar</item>
+      <item name="alertDialogTheme">@style/Dialog</item>
+   </style>
+
+   <style name="ActionBar" parent="@style/Widget.AppCompat.ActionBar.Solid">
+      <item name="background">@color/e_action_bar</item>
+   </style>
+
+   <style name="Dialog" parent="Theme.AppCompat.DayNight.Dialog.Alert">
+      <item name="android:background">@color/e_floating_background</item>
+      <item name="android:colorAccent">@color/e_accent</item>
+   </style>
+</resources>
diff --git a/build.gradle b/build.gradle
index 1971eb582dc5da5fc1db3ec5096be02c509fcd68..b2ecd603a6b3f341c71dd241f8bf603f281a9ff0 100755
--- a/build.gradle
+++ b/build.gradle
@@ -41,6 +41,7 @@ buildscript {
 
 allprojects {
     repositories {
+        maven { url 'https://gitlab.e.foundation/api/v4/groups/9/-/packages/maven'}
         maven { url "https://jitpack.io" }
         google()
         jcenter()