diff --git a/app/src/main/java/me/impy/aegis/ui/AegisActivity.java b/app/src/main/java/me/impy/aegis/ui/AegisActivity.java
index 95a3a856..55c1ca77 100644
--- a/app/src/main/java/me/impy/aegis/ui/AegisActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/AegisActivity.java
@@ -18,13 +18,13 @@ public abstract class AegisActivity extends AppCompatActivity {
         getWindow().setFlags(WindowManager.LayoutParams.FLAG_SECURE, WindowManager.LayoutParams.FLAG_SECURE);
 
         // set the theme
-        boolean nightMode = _app.getPreferences().getBoolean("pref_dark_mode", false);
-        setPreferredTheme(nightMode);
+        boolean darkMode = _app.getPreferences().getBoolean("pref_dark_mode", false);
+        setPreferredTheme(darkMode);
     }
 
     protected AegisApplication getApp() {
         return _app;
     }
 
-    protected abstract void setPreferredTheme(boolean nightMode);
+    protected abstract void setPreferredTheme(boolean darkMode);
 }
diff --git a/app/src/main/java/me/impy/aegis/ui/AuthActivity.java b/app/src/main/java/me/impy/aegis/ui/AuthActivity.java
index 8ca30f7d..7f5246c3 100644
--- a/app/src/main/java/me/impy/aegis/ui/AuthActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/AuthActivity.java
@@ -103,8 +103,8 @@ public class AuthActivity extends AegisActivity implements FingerprintUiHelper.C
     }
 
     @Override
-    protected void setPreferredTheme(boolean nightMode) {
-        if (nightMode) {
+    protected void setPreferredTheme(boolean darkMode) {
+        if (darkMode) {
             setTheme(R.style.AppTheme_Dark);
         } else {
             setTheme(R.style.AppTheme_Default);
diff --git a/app/src/main/java/me/impy/aegis/ui/EditProfileActivity.java b/app/src/main/java/me/impy/aegis/ui/EditProfileActivity.java
index bd6d569f..e148a9c6 100644
--- a/app/src/main/java/me/impy/aegis/ui/EditProfileActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/EditProfileActivity.java
@@ -156,8 +156,8 @@ public class EditProfileActivity extends AegisActivity {
     }
 
     @Override
-    protected void setPreferredTheme(boolean nightMode) {
-        if (nightMode) {
+    protected void setPreferredTheme(boolean darkMode) {
+        if (darkMode) {
             _dialogStyle = android.R.style.Theme_Material_Dialog_NoActionBar;
             setTheme(R.style.AppTheme_Dark_TransparentActionBar);
         } else {
diff --git a/app/src/main/java/me/impy/aegis/ui/MainActivity.java b/app/src/main/java/me/impy/aegis/ui/MainActivity.java
index 481dabd6..02a1e1b4 100644
--- a/app/src/main/java/me/impy/aegis/ui/MainActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/MainActivity.java
@@ -7,7 +7,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.graphics.Rect;
 import android.support.design.widget.BottomSheetDialog;
-import android.support.v7.app.AlertDialog;
 import android.os.Bundle;
 import android.view.Menu;
 import android.view.MenuItem;
@@ -48,7 +47,7 @@ public class MainActivity extends AegisActivity implements KeyProfileView.Listen
     private DatabaseManager _db;
     private KeyProfileView _keyProfileView;
 
-    private boolean _nightMode = false;
+    private boolean _darkMode = false;
     private Menu _menu;
     private FloatingActionsMenu _fabMenu;
 
@@ -139,13 +138,13 @@ public class MainActivity extends AegisActivity implements KeyProfileView.Listen
     }
 
     @Override
-    protected void setPreferredTheme(boolean nightMode) {
-        if (nightMode) {
+    protected void setPreferredTheme(boolean darkMode) {
+        if (darkMode) {
             setTheme(R.style.AppTheme_Dark_NoActionBar);
-        } else if (_nightMode) {
+        } else if (_darkMode) {
             setTheme(R.style.AppTheme_Default_NoActionBar);
         }
-        _nightMode = nightMode;
+        _darkMode = darkMode;
     }
 
     @Override
@@ -346,9 +345,9 @@ public class MainActivity extends AegisActivity implements KeyProfileView.Listen
     protected void onResume() {
         super.onResume();
 
-        boolean nightMode = _app.getPreferences().getBoolean("pref_dark_mode", false);
-        if (nightMode != _nightMode) {
-            setPreferredTheme(nightMode);
+        boolean darkMode = _app.getPreferences().getBoolean("pref_dark_mode", false);
+        if (darkMode != _darkMode) {
+            setPreferredTheme(darkMode);
             recreate();
         }
 
diff --git a/app/src/main/java/me/impy/aegis/ui/PreferencesActivity.java b/app/src/main/java/me/impy/aegis/ui/PreferencesActivity.java
index e3c8f095..e4e0fadc 100644
--- a/app/src/main/java/me/impy/aegis/ui/PreferencesActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/PreferencesActivity.java
@@ -17,8 +17,8 @@ public class PreferencesActivity extends AegisActivity {
     }
 
     @Override
-    protected void setPreferredTheme(boolean nightMode) {
-        if (nightMode) {
+    protected void setPreferredTheme(boolean darkMode) {
+        if (darkMode) {
             setTheme(R.style.AppTheme_Dark);
         } else {
             setTheme(R.style.AppTheme_Default);
diff --git a/app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java b/app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java
index e4e4c149..a1fe69b5 100644
--- a/app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java
+++ b/app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java
@@ -69,11 +69,11 @@ public class PreferencesFragment extends PreferenceFragment {
         // set the result intent in advance
         setResult();
 
-        Preference nightModePreference = findPreference("pref_dark_mode");
-        nightModePreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
+        Preference darkModePreference = findPreference("pref_dark_mode");
+        darkModePreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
             @Override
             public boolean onPreferenceChange(Preference preference, Object newValue) {
-                Toast.makeText(getActivity(), "Night mode will be enabled after closing this screen", Toast.LENGTH_SHORT).show();
+                Toast.makeText(getActivity(), "Dark mode setting will be applied after closing this screen", Toast.LENGTH_SHORT).show();
                 return true;
             }
         });
diff --git a/app/src/main/java/me/impy/aegis/ui/SlotManagerActivity.java b/app/src/main/java/me/impy/aegis/ui/SlotManagerActivity.java
index a31d459c..fa4109ad 100644
--- a/app/src/main/java/me/impy/aegis/ui/SlotManagerActivity.java
+++ b/app/src/main/java/me/impy/aegis/ui/SlotManagerActivity.java
@@ -103,8 +103,8 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
     }
 
     @Override
-    protected void setPreferredTheme(boolean nightMode) {
-        if (nightMode) {
+    protected void setPreferredTheme(boolean darkMode) {
+        if (darkMode) {
             setTheme(R.style.AppTheme_Dark_NoActionBar);
         } else {
             setTheme(R.style.AppTheme_Default_NoActionBar);