diff --git a/static/app-strings.json b/static/app-strings.json
index 2519ea806..daa35ab0a 100644
--- a/static/app-strings.json
+++ b/static/app-strings.json
@@ -2225,5 +2225,6 @@
   "Buy LBC": "Buy LBC",
   "This is information like error logging, performance tracking, and usage statistics. It includes your IP address and basic system details, but no other identifying information (unless you connect to a cloud service)": "This is information like error logging, performance tracking, and usage statistics. It includes your IP address and basic system details, but no other identifying information (unless you connect to a cloud service)",
   "Use official LBRY wallet servers": "Use official LBRY wallet servers",
+  "Enable Prerelease Updates": "Enable Prerelease Updates",
   "--end--": "--end--"
 }
diff --git a/ui/component/settingEnablePrereleases/index.js b/ui/component/settingEnablePrereleases/index.js
new file mode 100644
index 000000000..0db6ad3b9
--- /dev/null
+++ b/ui/component/settingEnablePrereleases/index.js
@@ -0,0 +1,17 @@
+import SettingEnablePrereleases from './view';
+import * as SETTINGS from 'constants/settings';
+import { connect } from 'react-redux';
+import { makeSelectClientSetting } from 'redux/selectors/settings';
+import { doSetClientSetting } from 'redux/actions/settings';
+
+const select = (state) => {
+  return {
+    enablePrereleases: makeSelectClientSetting(SETTINGS.ENABLE_PRERELEASE_UPDATES)(state),
+  };
+};
+
+const perform = (dispatch) => ({
+  setClientSetting: (value) => dispatch(doSetClientSetting(SETTINGS.ENABLE_PRERELEASE_UPDATES, value)),
+});
+
+export default connect(select, perform)(SettingEnablePrereleases);
diff --git a/ui/component/settingEnablePrereleases/view.jsx b/ui/component/settingEnablePrereleases/view.jsx
new file mode 100644
index 000000000..7866b6bbc
--- /dev/null
+++ b/ui/component/settingEnablePrereleases/view.jsx
@@ -0,0 +1,25 @@
+// @flow
+import React from 'react';
+import { FormField } from 'component/common/form';
+
+type Props = {
+  setClientSetting: (boolean) => void,
+  enablePrereleases: boolean,
+};
+function SettingEnablePrereleases(props: Props) {
+  const { setClientSetting, enablePrereleases } = props;
+  return (
+    <React.Fragment>
+      <FormField
+        type="checkbox"
+        name="prereleases"
+        onChange={() => {
+          setClientSetting(!enablePrereleases);
+        }}
+        checked={enablePrereleases}
+      />
+    </React.Fragment>
+  );
+}
+
+export default SettingEnablePrereleases;
diff --git a/ui/component/settingSystem/view.jsx b/ui/component/settingSystem/view.jsx
index dcc4f92e4..617b60905 100644
--- a/ui/component/settingSystem/view.jsx
+++ b/ui/component/settingSystem/view.jsx
@@ -17,10 +17,9 @@ import Spinner from 'component/spinner';
 import { getPasswordFromCookie } from 'util/saved-passwords';
 import * as DAEMON_SETTINGS from 'constants/daemon_settings';
 import { formatBytes } from 'util/format-bytes';
+import SettingEnablePrereleases from 'component/settingEnablePrereleases';
 
-// @if TARGET='app'
 const IS_MAC = process.platform === 'darwin';
-// @endif
 const BYTES_PER_MB = 1048576;
 
 type Price = {
@@ -96,10 +95,7 @@ export default function SettingSystem(props: Props) {
   const [blobSpaceLimitGB, setBlobSpaceLimit] = React.useState(blobLimitSetting ? blobLimitSetting / 1024 : 0);
   // const debouncedBlobSpaceLimitGB = useDebounce(blobSpaceLimitGB || 0, 500);
   const [limitSpace, setLimitSpace] = React.useState(Boolean(blobLimitSetting));
-  console.log('spaceUsed', spaceUsed, 'blobLimit', blobLimitSetting);
-  // @if TARGET='app'
   const { available: ffmpegAvailable, which: ffmpegPath } = ffmpegStatus;
-  // @endif
 
   function onChangeEncryptWallet() {
     if (walletEncrypted) {
@@ -140,7 +136,6 @@ export default function SettingSystem(props: Props) {
 
   // Update ffmpeg variables
   React.useEffect(() => {
-    // @if TARGET='app'
     const { available } = ffmpegStatus;
     const { ffmpeg_path: ffmpegPath } = daemonSettings;
     if (!available) {
@@ -149,7 +144,6 @@ export default function SettingSystem(props: Props) {
       }
       findFFmpeg();
     }
-    // @endif
   }, []); // eslint-disable-line react-hooks/exhaustive-deps
 
   // Update storedPassword state
@@ -186,7 +180,6 @@ export default function SettingSystem(props: Props) {
             </SettingsRow>
             {/* @endif */}
 
-            {/* @if TARGET='app' */}
             <SettingsRow
               title={__('Save all viewed content to your downloads directory')}
               subtitle={__(
@@ -259,9 +252,6 @@ export default function SettingSystem(props: Props) {
                 />
               )}
             </SettingsRow>
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
             <SettingsRow
               title={__('Share usage and diagnostic data')}
               subtitle={
@@ -296,9 +286,6 @@ export default function SettingSystem(props: Props) {
                 helper={__('We use detailed analytics to improve all aspects of the LBRY experience.')}
               />
             </SettingsRow>
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
             {/* Auto launch in a hidden state doesn't work on mac https://github.com/Teamwork/node-auto-launch/issues/81 */}
             {!IS_MAC && (
               <SettingsRow
@@ -310,15 +297,15 @@ export default function SettingSystem(props: Props) {
                 <SettingAutoLaunch noLabels />
               </SettingsRow>
             )}
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
             <SettingsRow title={__('Leave app running in notification area when the window is closed')}>
               <SettingClosingBehavior noLabels />
             </SettingsRow>
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
+            <SettingsRow
+              title={__('Enable Upgrade to Test Builds')}
+              subtitle={__('Prereleases may break things and we may not be able to fix them for you.')}
+            >
+              <SettingEnablePrereleases />
+            </SettingsRow>
             <SettingsRow
               title={
                 <span>
@@ -379,9 +366,6 @@ export default function SettingSystem(props: Props) {
                 )}
               </p>
             </SettingsRow>
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
             <SettingsRow
               title={__('Encrypt my wallet with a custom password')}
               subtitle={
@@ -424,9 +408,6 @@ export default function SettingSystem(props: Props) {
                 />
               </SettingsRow>
             )}
-            {/* @endif */}
-
-            {/* @if TARGET='app' */}
             <SettingsRow
               title={__('Max connections')}
               subtitle={__(
@@ -475,8 +456,6 @@ export default function SettingSystem(props: Props) {
             <SettingsRow title={__('Share url')} multirow>
               <SettingShareUrl />
             </SettingsRow>
-            {/* @endif */}
-
             <SettingsRow
               title={__('Clear application cache')}
               subtitle={__('This might fix issues that you are having. Your wallet will not be affected.')}
diff --git a/ui/component/viewers/videoViewer/internal/plugins/videojs-mobile-ui/touchOverlay.js b/ui/component/viewers/videoViewer/internal/plugins/videojs-mobile-ui/touchOverlay.js
index 8dd112926..00fe9271d 100644
--- a/ui/component/viewers/videoViewer/internal/plugins/videojs-mobile-ui/touchOverlay.js
+++ b/ui/component/viewers/videoViewer/internal/plugins/videojs-mobile-ui/touchOverlay.js
@@ -34,7 +34,7 @@ class TouchOverlay extends Component {
     this.addChild('playToggle', {});
 
     // Clear overlay when playback starts or with control fade
-    player.on(['playing', 'userinactive'], (e) => {
+    player.on(['playing', 'userinactive'], e => {
       if (!this.player_.paused()) {
         this.removeClass('show-play-toggle');
       }
@@ -104,6 +104,27 @@ class TouchOverlay extends Component {
   handleSingleTap(event) {
     this.removeClass('skip');
     this.toggleClass('show-play-toggle');
+
+    // At the moment, we only have one <video> tag at a time, but just loops it
+    // all to somewhat future-proof it.
+    const videos = document.getElementsByTagName('video');
+    for (let video of videos) {
+      // The Android-Chrome cast button appears when you tap directly on the
+      // video. If anything exists above it, such as our mobile-ui overlay, the
+      // action will be absorbed, causing the button to not appear. So, I've
+      // tried to pass on the tap event by manually dispatching one, but it
+      // didn't work.
+      // Peeking at the Android-Chrome code, the cast button is refreshed when
+      // the 'controllist' is updated. Since we don't use this attribute as we
+      // are using the videojs controls, I'm "toggling" this attribute to force
+      // the cast button to be refreshed.
+      const attr = video.getAttribute('controlslist');
+      if (!attr || attr.indexOf('dummy') === -1) {
+        video.setAttribute('controlslist', 'dummy');
+      } else {
+        video.removeAttribute('controlslist');
+      }
+    }
   }
 
   /**
diff --git a/ui/constants/settings.js b/ui/constants/settings.js
index 9dc673549..72363de04 100644
--- a/ui/constants/settings.js
+++ b/ui/constants/settings.js
@@ -43,6 +43,7 @@ export const CUSTOM_COMMENTS_SERVER_ENABLED = 'custom_comments_server_enabled';
 export const CUSTOM_COMMENTS_SERVER_URL = 'custom_comments_server_url';
 export const CUSTOM_SHARE_URL_ENABLED = 'custom_share_url_enabled';
 export const CUSTOM_SHARE_URL = 'custom_share_url';
+export const ENABLE_PRERELEASE_UPDATES = 'enable_prerelease_updates';
 
 export const SETTINGS_GRP = {
   APPEARANCE: 'appearance',
diff --git a/ui/index.jsx b/ui/index.jsx
index 93dd6435c..0f88a4900 100644
--- a/ui/index.jsx
+++ b/ui/index.jsx
@@ -11,6 +11,7 @@ import * as MODALS from 'constants/modal_types';
 import React, { Fragment, useState, useEffect } from 'react';
 import ReactDOM from 'react-dom';
 import { Provider } from 'react-redux';
+import * as SETTINGS from 'constants/settings';
 import {
   doDaemonReady,
   doAutoUpdate,
@@ -33,6 +34,7 @@ import { PersistGate } from 'redux-persist/integration/react';
 import analytics from 'analytics';
 import { doToast } from 'redux/actions/notifications';
 import { getAuthToken, setAuthToken, doAuthTokenRefresh } from 'util/saved-passwords';
+import { makeSelectClientSetting } from 'redux/selectors/settings';
 import { DEFAULT_LANGUAGE, LBRY_API_URL } from 'config';
 
 // Import 3rd-party styles before ours for the current way we are code-splitting.
@@ -185,6 +187,16 @@ function AppWrapper() {
   const [readyToLaunch, setReadyToLaunch] = useState(IS_WEB);
   const [persistDone, setPersistDone] = useState(false);
 
+  useEffect(() => {
+    if (persistDone) {
+      const state = store.getState();
+      const enabled = makeSelectClientSetting(SETTINGS.ENABLE_PRERELEASE_UPDATES)(state);
+      if (enabled) {
+        autoUpdater.allowPrerelease = true;
+      }
+    }
+  }, [persistDone]);
+
   useEffect(() => {
     // @if TARGET='app'
     moment.locale(remote.app.getLocale());
diff --git a/ui/redux/reducers/settings.js b/ui/redux/reducers/settings.js
index 966c61d36..7dcdf1c65 100644
--- a/ui/redux/reducers/settings.js
+++ b/ui/redux/reducers/settings.js
@@ -80,6 +80,7 @@ const defaultState = {
     // OS
     [SETTINGS.AUTO_LAUNCH]: true,
     [SETTINGS.TO_TRAY_WHEN_CLOSED]: true,
+    [SETTINGS.ENABLE_PRERELEASE_UPDATES]: false,
   },
 };
 defaultState.clientSettings[SETTINGS.AUTOPLAY_NEXT] = defaultState.clientSettings[SETTINGS.AUTOPLAY_MEDIA];
diff --git a/ui/scss/component/_file-render.scss b/ui/scss/component/_file-render.scss
index 5f95902bc..d43615d91 100644
--- a/ui/scss/component/_file-render.scss
+++ b/ui/scss/component/_file-render.scss
@@ -474,6 +474,42 @@
     &.skip {
       background-color: rgba(0, 0, 0, 0.5);
     }
+
+    // Override the original's 'display: block' to avoid the big play button
+    // from being squished to the side:
+    position: absolute;
+  }
+}
+
+video::-internal-media-controls-overlay-cast-button {
+  // Push the cast button above vjs-touch-overlay:
+  z-index: 3;
+
+  // Move it to the upper-right since it will clash with "tap to unmute":
+  left: unset;
+  right: 8px;
+}
+
+.video-js.video-js.vjs-user-inactive {
+  video::-internal-media-controls-overlay-cast-button {
+    // (1) Android-Chrome's original Cast button behavior:
+    // - If video is playing, fade out the button.
+    // - If video is paused and video is tapped, display the button and stay on.
+    // (2) We then injected another behavior:
+    // - Display the button when '.vjs-touch-overlay' is displayed. However,
+    // the 'controlslist' attribute hack that was used to do this results in the
+    // button staying displayed without a fade-out timer.
+    // (3) Ideally, we should sync the '.vjs-touch-overlay' visibility with the
+    // cast button, similar to how to controlBar's visibility is synced above.
+    // But I have no idea how to grab the sibling '.show-play-toggle' into the
+    // css logic.
+    // (4) So, this is the best that I can come up with: Whenever user is idle,
+    // the button goes away. The only downside I know is the scenario of
+    // "overlay is up and video is paused, but button goes away due to idle".
+    // The user just needs to re-tap any empty space on the overlay to get the
+    // Cast button again.
+    opacity: 0;
+    transition: opacity 1s ease;
   }
 }