--- a/mobile/android/app/src/main/res/xml/preferences_advanced.xml
+++ b/mobile/android/app/src/main/res/xml/preferences_advanced.xml
@@ -90,11 +90,16 @@
             android:summary="@string/pref_activity_stream_summary" />
 
 
         <SwitchPreference android:key="android.not_a_preference.customtabs"
             android:title="@string/pref_custom_tabs"
             android:summary="@string/pref_custom_tabs_summary"
             android:defaultValue="false" />
 
+        <SwitchPreference android:key="android.not_a_preference.pwa"
+            android:title="@string/pref_pwa"
+            android:summary="@string/pref_pwa_summary"
+            android:defaultValue="false" />
+
     </PreferenceCategory>
 
 </PreferenceScreen>

--- a/mobile/android/base/AppConstants.java.in
+++ b/mobile/android/base/AppConstants.java.in
@@ -305,16 +305,23 @@ public class AppConstants {
 
     public static final boolean MOZ_ANDROID_CUSTOM_TABS =
 //#ifdef MOZ_ANDROID_CUSTOM_TABS
     true;
 //#else
     false;
 //#endif
 
+    public static final boolean MOZ_ANDROID_PWA =
+//#ifdef MOZ_ANDROID_PWA
+    true;
+//#else
+    false;
+//#endif
+
     // (bug 1266820) Temporarily disabled since no one is working on it.
     public static final boolean SCREENSHOTS_IN_BOOKMARKS_ENABLED = false;
 
     public static final boolean MOZ_ANDROID_ACTIVITY_STREAM =
 //#ifdef MOZ_ANDROID_ACTIVITY_STREAM
         true;
 //#else
         false;

--- a/mobile/android/base/generate_build_config.py
+++ b/mobile/android/base/generate_build_config.py
@@ -42,16 +42,17 @@ def _defines():
                 'MOZ_ANDROID_CUSTOM_TABS',
                 'MOZ_ANDROID_DOWNLOADS_INTEGRATION',
                 'MOZ_ANDROID_DOWNLOAD_CONTENT_SERVICE',
                 'MOZ_ANDROID_EXCLUDE_FONTS',
                 'MOZ_ANDROID_GCM',
                 'MOZ_ANDROID_MLS_STUMBLER',
                 'MOZ_ANDROID_MMA',
                 'MOZ_ANDROID_MOZILLA_ONLINE',
+                'MOZ_ANDROID_PWA',
                 'MOZ_LEANPLUM_SDK_KEY',
                 'MOZ_LEANPLUM_SDK_CLIENTID',
                 'MOZ_ANDROID_SEARCH_ACTIVITY',
                 'MOZ_CRASHREPORTER',
                 'MOZ_DEBUG',
                 'MOZ_INSTALL_TRACKING',
                 'MOZ_NATIVE_DEVICES',
                 'MOZ_SWITCHBOARD'):

--- a/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java
+++ b/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java
@@ -157,16 +157,17 @@ public class GeckoPreferences
     private static final String PREFS_FEEDBACK_LINK = NON_PREF_PREFIX + "feedback.link";
     public static final String PREFS_NOTIFICATIONS_CONTENT = NON_PREF_PREFIX + "notifications.content";
     public static final String PREFS_NOTIFICATIONS_CONTENT_LEARN_MORE = NON_PREF_PREFIX + "notifications.content.learn_more";
     public static final String PREFS_NOTIFICATIONS_WHATS_NEW = NON_PREF_PREFIX + "notifications.whats_new";
     public static final String PREFS_APP_UPDATE_LAST_BUILD_ID = "app.update.last_build_id";
     public static final String PREFS_READ_PARTNER_CUSTOMIZATIONS_PROVIDER = NON_PREF_PREFIX + "distribution.read_partner_customizations_provider";
     public static final String PREFS_READ_PARTNER_BOOKMARKS_PROVIDER = NON_PREF_PREFIX + "distribution.read_partner_bookmarks_provider";
     public static final String PREFS_CUSTOM_TABS = NON_PREF_PREFIX + "customtabs";
+    public static final String PREFS_PWA = NON_PREF_PREFIX + "pwa";
     public static final String PREFS_ACTIVITY_STREAM = NON_PREF_PREFIX + "experiments.activitystream";
     public static final String PREFS_CATEGORY_EXPERIMENTAL_FEATURES = NON_PREF_PREFIX + "category_experimental";
     public static final String PREFS_COMPACT_TABS = NON_PREF_PREFIX + "compact_tabs";
     public static final String PREFS_SHOW_QUIT_MENU = NON_PREF_PREFIX + "distribution.show_quit_menu";
     public static final String PREFS_SEARCH_SUGGESTIONS_ENABLED = "browser.search.suggest.enabled";
     public static final String PREFS_DEFAULT_BROWSER = NON_PREF_PREFIX + "default_browser.link";
     public static final String PREFS_SYSTEM_FONT_SIZE = NON_PREF_PREFIX + "font.size.use_system_font_size";
     public static final String PREFS_SET_AS_HOMEPAGE = NON_PREF_PREFIX + "distribution.set_as_homepage";
@@ -668,16 +669,17 @@ public class GeckoPreferences
                         continue;
                     }
                 } else if (PREFS_SCREEN_ADVANCED.equals(key) &&
                         !Restrictions.isAllowed(this, Restrictable.ADVANCED_SETTINGS)) {
                     preferences.removePreference(pref);
                     i--;
                     continue;
                 } else if (PREFS_CATEGORY_EXPERIMENTAL_FEATURES.equals(key)
+                        && !AppConstants.MOZ_ANDROID_PWA
                         && !AppConstants.MOZ_ANDROID_CUSTOM_TABS
                         && !ActivityStream.isUserSwitchable(this)) {
                     preferences.removePreference(pref);
                     i--;
                     continue;
                 }
                 setupPreferences((PreferenceGroup) pref, prefs);
             } else {
@@ -863,16 +865,20 @@ public class GeckoPreferences
                         preferences.removePreference(pref);
                         i--;
                         continue;
                     }
                 } else if (PREFS_CUSTOM_TABS.equals(key) && !AppConstants.MOZ_ANDROID_CUSTOM_TABS) {
                     preferences.removePreference(pref);
                     i--;
                     continue;
+                } else if (PREFS_PWA.equals(key) && !AppConstants.MOZ_ANDROID_PWA) {
+                    preferences.removePreference(pref);
+                    i--;
+                    continue;
                 } else if (PREFS_ACTIVITY_STREAM.equals(key)
                         && !ActivityStream.isUserSwitchable(this)) {
                     preferences.removePreference(pref);
                     i--;
                     continue;
                 } else if (PREFS_COMPACT_TABS.equals(key)) {
                     if (HardwareUtils.isTablet()) {
                         preferences.removePreference(pref);

--- a/mobile/android/base/locales/en-US/android_strings.dtd
+++ b/mobile/android/base/locales/en-US/android_strings.dtd
@@ -290,16 +290,19 @@
 <!ENTITY pref_custom_tabs_summary3 "Allow apps to open websites using a customized version of &brandShortName;">
 <!-- Localization note (custom_tabs_menu_item_open_in): The variable is replaced by the name of
      default browser from user's preference, such as "Open in Firefox" -->
 <!ENTITY custom_tabs_menu_item_open_in "Open in &formatS;">
 <!ENTITY custom_tabs_menu_footer "Powered by &brandShortName;">
 <!-- Long-click title of CustomTabsActivity will copy URL to clipboard and display this hint -->
 <!ENTITY custom_tabs_hint_url_copy "URL copied">
 
+<!ENTITY pref_pwa "Progressive Web Apps">
+<!ENTITY pref_pwa_summary "Allow web apps to be added to home screen">
+
 <!-- Localization note (pref_activity_stream): Experimental feature, see https://testpilot.firefox.com/experiments/activity-stream  -->
 <!ENTITY pref_activity_stream "Activity Stream">
 <!ENTITY pref_activity_stream_summary "A rich visual history feed and a reimagined home page make it easier than ever to find exactly what you\'re looking for in &brandShortName;.">
 
 <!ENTITY tracking_protection_prompt_title "Now with Tracking Protection">
 <!ENTITY tracking_protection_prompt_text "Actively block tracking elements so you don\'t have to worry.">
 <!ENTITY tracking_protection_prompt_tip_text "Visit Privacy settings to learn more">
 <!ENTITY tracking_protection_prompt_action_button "Got it!">

--- a/mobile/android/base/strings.xml.in
+++ b/mobile/android/base/strings.xml.in
@@ -242,16 +242,19 @@
   <string name="pref_category_experimental">&pref_category_experimental;</string>
 
   <string name="pref_custom_tabs">&pref_custom_tabs;</string>
   <string name="pref_custom_tabs_summary">&pref_custom_tabs_summary3;</string>
   <string name="custom_tabs_menu_item_open_in">&custom_tabs_menu_item_open_in;</string>
   <string name="custom_tabs_menu_footer">&custom_tabs_menu_footer;</string>
   <string name="custom_tabs_hint_url_copy">&custom_tabs_hint_url_copy;</string>
 
+  <string name="pref_pwa">&pref_pwa;</string>
+  <string name="pref_pwa_summary">&pref_pwa_summary;</string>
+
   <string name="pref_activity_stream">&pref_activity_stream;</string>
   <string name="pref_activity_stream_summary">&pref_activity_stream_summary;</string>
 
   <string name="pref_char_encoding">&pref_char_encoding;</string>
   <string name="pref_char_encoding_on">&pref_char_encoding_on;</string>
   <string name="pref_char_encoding_off">&pref_char_encoding_off;</string>
   <string name="pref_clear_private_data_now">&pref_clear_private_data2;</string>
   <string name="pref_clear_private_data_now_tablet">&pref_clear_private_data_now_tablet;</string>

--- a/mobile/android/moz.configure
+++ b/mobile/android/moz.configure
@@ -63,16 +63,20 @@ project_flag('MOZ_ANDROID_MLS_STUMBLER',
 project_flag('MOZ_ANDROID_DOWNLOAD_CONTENT_SERVICE',
              help='Background service for downloading additional content at runtime',
              default=True)
 
 project_flag('MOZ_ANDROID_CUSTOM_TABS',
              help='Enable support for Android custom tabs',
              default=milestone.is_nightly)
 
+project_flag('MOZ_ANDROID_PWA',
+             help='Enable support for Progressive Web Apps',
+             default=milestone.is_nightly)
+
 # Enable the Switchboard A/B framework code.
 # Note: The framework is always included in the app. This flag controls
 # usage of the framework.
 project_flag('MOZ_SWITCHBOARD',
              help='Include Switchboard A/B framework on Android',
              default=True)
 
 project_flag('MOZ_ANDROID_HLS_SUPPORT',