diff --git a/App.js b/App.tsx
similarity index 93%
rename from App.js
rename to App.tsx
index 467779b..8c32968 100644
--- a/App.js
+++ b/App.tsx
@@ -17,8 +17,6 @@
  * along with Campus INSAT.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-// @flow
-
 import * as React from 'react';
 import {LogBox, Platform, SafeAreaView, View} from 'react-native';
 import {NavigationContainer} from '@react-navigation/native';
@@ -28,7 +26,6 @@ import SplashScreen from 'react-native-splash-screen';
 import {OverflowMenuProvider} from 'react-navigation-header-buttons';
 import AsyncStorageManager from './src/managers/AsyncStorageManager';
 import CustomIntroSlider from './src/components/Overrides/CustomIntroSlider';
-import type {CustomThemeType} from './src/managers/ThemeManager';
 import ThemeManager from './src/managers/ThemeManager';
 import MainNavigator from './src/navigation/MainNavigator';
 import AprilFoolsManager from './src/managers/AprilFoolsManager';
@@ -38,6 +35,7 @@ import type {ParsedUrlDataType} from './src/utils/URLHandler';
 import URLHandler from './src/utils/URLHandler';
 import {setupStatusBar} from './src/utils/Utils';
 import initLocales from './src/utils/Locales';
+import {NavigationContainerRef} from '@react-navigation/core';
 
 // Native optimizations https://reactnavigation.org/docs/react-native-screens
 // Crashes app when navigating away from webview on android 9+
@@ -50,15 +48,15 @@ LogBox.ignoreLogs([
 ]);
 
 type StateType = {
-  isLoading: boolean,
-  showIntro: boolean,
-  showUpdate: boolean,
-  showAprilFools: boolean,
-  currentTheme: CustomThemeType | null,
+  isLoading: boolean;
+  showIntro: boolean;
+  showUpdate: boolean;
+  showAprilFools: boolean;
+  currentTheme: ReactNativePaper.Theme | undefined;
 };
 
 export default class App extends React.Component<null, StateType> {
-  navigatorRef: {current: null | NavigationContainer};
+  navigatorRef: {current: null | NavigationContainerRef};
 
   defaultHomeRoute: string | null;
 
@@ -67,13 +65,13 @@ export default class App extends React.Component<null, StateType> {
   urlHandler: URLHandler;
 
   constructor() {
-    super();
+    super(null);
     this.state = {
       isLoading: true,
       showIntro: true,
       showUpdate: true,
       showAprilFools: false,
-      currentTheme: null,
+      currentTheme: undefined,
     };
     initLocales();
     this.navigatorRef = React.createRef();
@@ -155,8 +153,11 @@ export default class App extends React.Component<null, StateType> {
     // Only show intro if this is the first time starting the app
     ThemeManager.getInstance().setUpdateThemeCallback(this.onUpdateTheme);
     // Status bar goes dark if set too fast on ios
-    if (Platform.OS === 'ios') setTimeout(setupStatusBar, 1000);
-    else setupStatusBar();
+    if (Platform.OS === 'ios') {
+      setTimeout(setupStatusBar, 1000);
+    } else {
+      setupStatusBar();
+    }
 
     this.setState({
       isLoading: false,
@@ -192,7 +193,7 @@ export default class App extends React.Component<null, StateType> {
   /**
    * Renders the app based on loading state
    */
-  render(): React.Node {
+  render() {
     const {state} = this;
     if (state.isLoading) {
       return null;
diff --git a/src/managers/AsyncStorageManager.js b/src/managers/AsyncStorageManager.ts
similarity index 86%
rename from src/managers/AsyncStorageManager.js
rename to src/managers/AsyncStorageManager.ts
index 5b5b5ca..483d0c8 100644
--- a/src/managers/AsyncStorageManager.js
+++ b/src/managers/AsyncStorageManager.ts
@@ -17,8 +17,6 @@
  * along with Campus INSAT.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-// @flow
-
 import AsyncStorage from '@react-native-community/async-storage';
 import {SERVICES_KEY} from './ServicesManager';
 
@@ -31,7 +29,7 @@ import {SERVICES_KEY} from './ServicesManager';
 export default class AsyncStorageManager {
   static instance: AsyncStorageManager | null = null;
 
-  static PREFERENCES = {
+  static PREFERENCES: {[key: string]: {key: string; default: string}} = {
     debugUnlocked: {
       key: 'debugUnlocked',
       default: '0',
@@ -132,10 +130,10 @@ export default class AsyncStorageManager {
     },
   };
 
-  #currentPreferences: {[key: string]: string};
+  private currentPreferences: {[key: string]: string};
 
   constructor() {
-    this.#currentPreferences = {};
+    this.currentPreferences = {};
   }
 
   /**
@@ -143,8 +141,9 @@ export default class AsyncStorageManager {
    * @returns {AsyncStorageManager}
    */
   static getInstance(): AsyncStorageManager {
-    if (AsyncStorageManager.instance == null)
+    if (AsyncStorageManager.instance == null) {
       AsyncStorageManager.instance = new AsyncStorageManager();
+    }
     return AsyncStorageManager.instance;
   }
 
@@ -156,8 +155,7 @@ export default class AsyncStorageManager {
    */
   static set(
     key: string,
-    // eslint-disable-next-line flowtype/no-weak-types
-    value: number | string | boolean | {...} | Array<any>,
+    value: number | string | boolean | object | Array<any>,
   ) {
     AsyncStorageManager.getInstance().setPreference(key, value);
   }
@@ -200,8 +198,7 @@ export default class AsyncStorageManager {
    * @param key
    * @returns {{...}}
    */
-  // eslint-disable-next-line flowtype/no-weak-types
-  static getObject(key: string): any {
+  static getObject(key: string): object | Array<any> {
     return JSON.parse(AsyncStorageManager.getString(key));
   }
 
@@ -212,7 +209,7 @@ export default class AsyncStorageManager {
    * @return {Promise<void>}
    */
   async loadPreferences() {
-    const prefKeys = [];
+    const prefKeys: Array<string> = [];
     // Get all available keys
     Object.keys(AsyncStorageManager.PREFERENCES).forEach((key: string) => {
       prefKeys.push(key);
@@ -223,8 +220,10 @@ export default class AsyncStorageManager {
     resultArray.forEach((item: [string, string | null]) => {
       const key = item[0];
       let val = item[1];
-      if (val === null) val = AsyncStorageManager.PREFERENCES[key].default;
-      this.#currentPreferences[key] = val;
+      if (val === null) {
+        val = AsyncStorageManager.PREFERENCES[key].default;
+      }
+      this.currentPreferences[key] = val;
     });
   }
 
@@ -237,16 +236,18 @@ export default class AsyncStorageManager {
    */
   setPreference(
     key: string,
-    // eslint-disable-next-line flowtype/no-weak-types
-    value: number | string | boolean | {...} | Array<any>,
+    value: number | string | boolean | object | Array<any>,
   ) {
     if (AsyncStorageManager.PREFERENCES[key] != null) {
       let convertedValue;
-      if (typeof value === 'string') convertedValue = value;
-      else if (typeof value === 'boolean' || typeof value === 'number')
+      if (typeof value === 'string') {
+        convertedValue = value;
+      } else if (typeof value === 'boolean' || typeof value === 'number') {
         convertedValue = value.toString();
-      else convertedValue = JSON.stringify(value);
-      this.#currentPreferences[key] = convertedValue;
+      } else {
+        convertedValue = JSON.stringify(value);
+      }
+      this.currentPreferences[key] = convertedValue;
       AsyncStorage.setItem(key, convertedValue);
     }
   }
@@ -259,6 +260,6 @@ export default class AsyncStorageManager {
    * @returns {string|null}
    */
   getPreference(key: string): string | null {
-    return this.#currentPreferences[key];
+    return this.currentPreferences[key];
   }
 }
diff --git a/src/managers/ThemeManager.js b/src/managers/ThemeManager.js
deleted file mode 100644
index 0b6872d..0000000
--- a/src/managers/ThemeManager.js
+++ /dev/null
@@ -1,307 +0,0 @@
-/*
- * Copyright (c) 2019 - 2020 Arnaud Vergnet.
- *
- * This file is part of Campus INSAT.
- *
- * Campus INSAT 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.
- *
- * Campus INSAT 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 Campus INSAT.  If not, see <https://www.gnu.org/licenses/>.
- */
-
-// @flow
-
-import {DarkTheme, DefaultTheme} from 'react-native-paper';
-import {Appearance} from 'react-native-appearance';
-import AsyncStorageManager from './AsyncStorageManager';
-import AprilFoolsManager from './AprilFoolsManager';
-
-const colorScheme = Appearance.getColorScheme();
-
-export type CustomThemeType = {
-  ...DefaultTheme,
-  colors: {
-    primary: string,
-    accent: string,
-    tabIcon: string,
-    card: string,
-    dividerBackground: string,
-    ripple: string,
-    textDisabled: string,
-    icon: string,
-    subtitle: string,
-    success: string,
-    warning: string,
-    danger: string,
-
-    // Calendar/Agenda
-    agendaBackgroundColor: string,
-    agendaDayTextColor: string,
-
-    // PROXIWASH
-    proxiwashFinishedColor: string,
-    proxiwashReadyColor: string,
-    proxiwashRunningColor: string,
-    proxiwashRunningNotStartedColor: string,
-    proxiwashRunningBgColor: string,
-    proxiwashBrokenColor: string,
-    proxiwashErrorColor: string,
-    proxiwashUnknownColor: string,
-
-    // Screens
-    planningColor: string,
-    proximoColor: string,
-    proxiwashColor: string,
-    menuColor: string,
-    tutorinsaColor: string,
-
-    // Tetris
-    tetrisBackground: string,
-    tetrisBorder: string,
-    tetrisScore: string,
-    tetrisI: string,
-    tetrisO: string,
-    tetrisT: string,
-    tetrisS: string,
-    tetrisZ: string,
-    tetrisJ: string,
-    tetrisL: string,
-
-    gameGold: string,
-    gameSilver: string,
-    gameBronze: string,
-
-    // Mascot Popup
-    mascotMessageArrow: string,
-  },
-};
-
-/**
- * Singleton class used to manage themes
- */
-export default class ThemeManager {
-  static instance: ThemeManager | null = null;
-
-  updateThemeCallback: null | (() => void);
-
-  constructor() {
-    this.updateThemeCallback = null;
-  }
-
-  /**
-   * Gets the light theme
-   *
-   * @return {CustomThemeType} Object containing theme variables
-   * */
-  static getWhiteTheme(): CustomThemeType {
-    return {
-      ...DefaultTheme,
-      colors: {
-        ...DefaultTheme.colors,
-        primary: '#be1522',
-        accent: '#be1522',
-        tabIcon: '#929292',
-        card: '#fff',
-        dividerBackground: '#e2e2e2',
-        ripple: 'rgba(0,0,0,0.2)',
-        textDisabled: '#c1c1c1',
-        icon: '#5d5d5d',
-        subtitle: '#707070',
-        success: '#5cb85c',
-        warning: '#f0ad4e',
-        danger: '#d9534f',
-        cc: 'dst',
-
-        // Calendar/Agenda
-        agendaBackgroundColor: '#f3f3f4',
-        agendaDayTextColor: '#636363',
-
-        // PROXIWASH
-        proxiwashFinishedColor: '#a5dc9d',
-        proxiwashReadyColor: 'transparent',
-        proxiwashRunningColor: '#a0ceff',
-        proxiwashRunningNotStartedColor: '#c9e0ff',
-        proxiwashRunningBgColor: '#c7e3ff',
-        proxiwashBrokenColor: '#ffa8a2',
-        proxiwashErrorColor: '#ffa8a2',
-        proxiwashUnknownColor: '#b6b6b6',
-
-        // Screens
-        planningColor: '#d9b10a',
-        proximoColor: '#ec5904',
-        proxiwashColor: '#1fa5ee',
-        menuColor: '#e91314',
-        tutorinsaColor: '#f93943',
-
-        // Tetris
-        tetrisBackground: '#f0f0f0',
-        tetrisScore: '#e2bd33',
-        tetrisI: '#3cd9e6',
-        tetrisO: '#ffdd00',
-        tetrisT: '#a716e5',
-        tetrisS: '#09c528',
-        tetrisZ: '#ff0009',
-        tetrisJ: '#2a67e3',
-        tetrisL: '#da742d',
-
-        gameGold: '#ffd610',
-        gameSilver: '#7b7b7b',
-        gameBronze: '#a15218',
-
-        // Mascot Popup
-        mascotMessageArrow: '#dedede',
-      },
-    };
-  }
-
-  /**
-   * Gets the dark theme
-   *
-   * @return {CustomThemeType} Object containing theme variables
-   * */
-  static getDarkTheme(): CustomThemeType {
-    return {
-      ...DarkTheme,
-      colors: {
-        ...DarkTheme.colors,
-        primary: '#be1522',
-        accent: '#be1522',
-        tabBackground: '#181818',
-        tabIcon: '#6d6d6d',
-        card: 'rgb(18,18,18)',
-        dividerBackground: '#222222',
-        ripple: 'rgba(255,255,255,0.2)',
-        textDisabled: '#5b5b5b',
-        icon: '#b3b3b3',
-        subtitle: '#aaaaaa',
-        success: '#5cb85c',
-        warning: '#f0ad4e',
-        danger: '#d9534f',
-
-        // Calendar/Agenda
-        agendaBackgroundColor: '#171717',
-        agendaDayTextColor: '#6d6d6d',
-
-        // PROXIWASH
-        proxiwashFinishedColor: '#31682c',
-        proxiwashReadyColor: 'transparent',
-        proxiwashRunningColor: '#213c79',
-        proxiwashRunningNotStartedColor: '#1e263e',
-        proxiwashRunningBgColor: '#1a2033',
-        proxiwashBrokenColor: '#7e2e2f',
-        proxiwashErrorColor: '#7e2e2f',
-        proxiwashUnknownColor: '#535353',
-
-        // Screens
-        planningColor: '#d99e09',
-        proximoColor: '#ec5904',
-        proxiwashColor: '#1fa5ee',
-        menuColor: '#b81213',
-        tutorinsaColor: '#f93943',
-
-        // Tetris
-        tetrisBackground: '#181818',
-        tetrisScore: '#e2d707',
-        tetrisI: '#30b3be',
-        tetrisO: '#c1a700',
-        tetrisT: '#9114c7',
-        tetrisS: '#08a121',
-        tetrisZ: '#b50008',
-        tetrisJ: '#0f37b9',
-        tetrisL: '#b96226',
-
-        gameGold: '#ffd610',
-        gameSilver: '#7b7b7b',
-        gameBronze: '#a15218',
-
-        // Mascot Popup
-        mascotMessageArrow: '#323232',
-      },
-    };
-  }
-
-  /**
-   * Get this class instance or create one if none is found
-   *
-   * @returns {ThemeManager}
-   */
-  static getInstance(): ThemeManager {
-    if (ThemeManager.instance == null)
-      ThemeManager.instance = new ThemeManager();
-    return ThemeManager.instance;
-  }
-
-  /**
-   * Gets night mode status.
-   * If Follow System Preferences is enabled, will first use system theme.
-   * If disabled or not available, will use value stored din preferences
-   *
-   * @returns {boolean} Night mode state
-   */
-  static getNightMode(): boolean {
-    return (
-      (AsyncStorageManager.getBool(
-        AsyncStorageManager.PREFERENCES.nightMode.key,
-      ) &&
-        (!AsyncStorageManager.getBool(
-          AsyncStorageManager.PREFERENCES.nightModeFollowSystem.key,
-        ) ||
-          colorScheme === 'no-preference')) ||
-      (AsyncStorageManager.getBool(
-        AsyncStorageManager.PREFERENCES.nightModeFollowSystem.key,
-      ) &&
-        colorScheme === 'dark')
-    );
-  }
-
-  /**
-   * Get the current theme based on night mode and events
-   *
-   * @returns {CustomThemeType} The current theme
-   */
-  static getCurrentTheme(): CustomThemeType {
-    if (AprilFoolsManager.getInstance().isAprilFoolsEnabled())
-      return AprilFoolsManager.getAprilFoolsTheme(ThemeManager.getWhiteTheme());
-    return ThemeManager.getBaseTheme();
-  }
-
-  /**
-   * Get the theme based on night mode
-   *
-   * @return {CustomThemeType} The theme
-   */
-  static getBaseTheme(): CustomThemeType {
-    if (ThemeManager.getNightMode()) return ThemeManager.getDarkTheme();
-    return ThemeManager.getWhiteTheme();
-  }
-
-  /**
-   * Sets the function to be called when the theme is changed (allows for general reload of the app)
-   *
-   * @param callback Function to call after theme change
-   */
-  setUpdateThemeCallback(callback: () => void) {
-    this.updateThemeCallback = callback;
-  }
-
-  /**
-   * Set night mode and save it to preferences
-   *
-   * @param isNightMode True to enable night mode, false to disable
-   */
-  setNightMode(isNightMode: boolean) {
-    AsyncStorageManager.set(
-      AsyncStorageManager.PREFERENCES.nightMode.key,
-      isNightMode,
-    );
-    if (this.updateThemeCallback != null) this.updateThemeCallback();
-  }
-}
diff --git a/src/managers/ThemeManager.ts b/src/managers/ThemeManager.ts
new file mode 100644
index 0000000..11c2b31
--- /dev/null
+++ b/src/managers/ThemeManager.ts
@@ -0,0 +1,298 @@
+/*
+ * Copyright (c) 2019 - 2020 Arnaud Vergnet.
+ *
+ * This file is part of Campus INSAT.
+ *
+ * Campus INSAT 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.
+ *
+ * Campus INSAT 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 Campus INSAT.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import {DarkTheme, DefaultTheme} from 'react-native-paper';
+import {Appearance} from 'react-native-appearance';
+import AsyncStorageManager from './AsyncStorageManager';
+import AprilFoolsManager from './AprilFoolsManager';
+
+const colorScheme = Appearance.getColorScheme();
+
+declare global {
+  namespace ReactNativePaper {
+    interface ThemeColors {
+      primary: string;
+      accent: string;
+      border: string;
+      tabIcon: string;
+      card: string;
+      dividerBackground: string;
+      ripple: string;
+      textDisabled: string;
+      icon: string;
+      subtitle: string;
+      success: string;
+      warning: string;
+      danger: string;
+
+      // Calendar/Agenda
+      agendaBackgroundColor: string;
+      agendaDayTextColor: string;
+
+      // PROXIWASH
+      proxiwashFinishedColor: string;
+      proxiwashReadyColor: string;
+      proxiwashRunningColor: string;
+      proxiwashRunningNotStartedColor: string;
+      proxiwashRunningBgColor: string;
+      proxiwashBrokenColor: string;
+      proxiwashErrorColor: string;
+      proxiwashUnknownColor: string;
+
+      // Screens
+      planningColor: string;
+      proximoColor: string;
+      proxiwashColor: string;
+      menuColor: string;
+      tutorinsaColor: string;
+
+      // Tetris
+      tetrisBackground: string;
+      tetrisScore: string;
+      tetrisI: string;
+      tetrisO: string;
+      tetrisT: string;
+      tetrisS: string;
+      tetrisZ: string;
+      tetrisJ: string;
+      tetrisL: string;
+
+      gameGold: string;
+      gameSilver: string;
+      gameBronze: string;
+
+      // Mascot Popup
+      mascotMessageArrow: string;
+    }
+  }
+}
+
+const CustomWhiteTheme: ReactNativePaper.Theme = {
+  ...DefaultTheme,
+  colors: {
+    ...DefaultTheme.colors,
+    primary: '#be1522',
+    accent: '#be1522',
+    border: '#e2e2e2',
+    tabIcon: '#929292',
+    card: '#fff',
+    dividerBackground: '#e2e2e2',
+    ripple: 'rgba(0,0,0,0.2)',
+    textDisabled: '#c1c1c1',
+    icon: '#5d5d5d',
+    subtitle: '#707070',
+    success: '#5cb85c',
+    warning: '#f0ad4e',
+    danger: '#d9534f',
+
+    // Calendar/Agenda
+    agendaBackgroundColor: '#f3f3f4',
+    agendaDayTextColor: '#636363',
+
+    // PROXIWASH
+    proxiwashFinishedColor: '#a5dc9d',
+    proxiwashReadyColor: 'transparent',
+    proxiwashRunningColor: '#a0ceff',
+    proxiwashRunningNotStartedColor: '#c9e0ff',
+    proxiwashRunningBgColor: '#c7e3ff',
+    proxiwashBrokenColor: '#ffa8a2',
+    proxiwashErrorColor: '#ffa8a2',
+    proxiwashUnknownColor: '#b6b6b6',
+
+    // Screens
+    planningColor: '#d9b10a',
+    proximoColor: '#ec5904',
+    proxiwashColor: '#1fa5ee',
+    menuColor: '#e91314',
+    tutorinsaColor: '#f93943',
+
+    // Tetris
+    tetrisBackground: '#f0f0f0',
+    tetrisScore: '#e2bd33',
+    tetrisI: '#3cd9e6',
+    tetrisO: '#ffdd00',
+    tetrisT: '#a716e5',
+    tetrisS: '#09c528',
+    tetrisZ: '#ff0009',
+    tetrisJ: '#2a67e3',
+    tetrisL: '#da742d',
+
+    gameGold: '#ffd610',
+    gameSilver: '#7b7b7b',
+    gameBronze: '#a15218',
+
+    // Mascot Popup
+    mascotMessageArrow: '#dedede',
+  },
+};
+
+const CustomDarkTheme: ReactNativePaper.Theme = {
+  ...DarkTheme,
+  colors: {
+    ...DarkTheme.colors,
+    primary: '#be1522',
+    accent: '#be1522',
+    border: '#222222',
+    tabIcon: '#6d6d6d',
+    card: 'rgb(18,18,18)',
+    dividerBackground: '#222222',
+    ripple: 'rgba(255,255,255,0.2)',
+    textDisabled: '#5b5b5b',
+    icon: '#b3b3b3',
+    subtitle: '#aaaaaa',
+    success: '#5cb85c',
+    warning: '#f0ad4e',
+    danger: '#d9534f',
+
+    // Calendar/Agenda
+    agendaBackgroundColor: '#171717',
+    agendaDayTextColor: '#6d6d6d',
+
+    // PROXIWASH
+    proxiwashFinishedColor: '#31682c',
+    proxiwashReadyColor: 'transparent',
+    proxiwashRunningColor: '#213c79',
+    proxiwashRunningNotStartedColor: '#1e263e',
+    proxiwashRunningBgColor: '#1a2033',
+    proxiwashBrokenColor: '#7e2e2f',
+    proxiwashErrorColor: '#7e2e2f',
+    proxiwashUnknownColor: '#535353',
+
+    // Screens
+    planningColor: '#d99e09',
+    proximoColor: '#ec5904',
+    proxiwashColor: '#1fa5ee',
+    menuColor: '#b81213',
+    tutorinsaColor: '#f93943',
+
+    // Tetris
+    tetrisBackground: '#181818',
+    tetrisScore: '#e2d707',
+    tetrisI: '#30b3be',
+    tetrisO: '#c1a700',
+    tetrisT: '#9114c7',
+    tetrisS: '#08a121',
+    tetrisZ: '#b50008',
+    tetrisJ: '#0f37b9',
+    tetrisL: '#b96226',
+
+    gameGold: '#ffd610',
+    gameSilver: '#7b7b7b',
+    gameBronze: '#a15218',
+
+    // Mascot Popup
+    mascotMessageArrow: '#323232',
+  },
+};
+
+/**
+ * Singleton class used to manage themes
+ */
+export default class ThemeManager {
+  static instance: ThemeManager | null = null;
+
+  updateThemeCallback: null | (() => void);
+
+  constructor() {
+    this.updateThemeCallback = null;
+  }
+
+  /**
+   * Get this class instance or create one if none is found
+   *
+   * @returns {ThemeManager}
+   */
+  static getInstance(): ThemeManager {
+    if (ThemeManager.instance == null) {
+      ThemeManager.instance = new ThemeManager();
+    }
+    return ThemeManager.instance;
+  }
+
+  /**
+   * Gets night mode status.
+   * If Follow System Preferences is enabled, will first use system theme.
+   * If disabled or not available, will use value stored din preferences
+   *
+   * @returns {boolean} Night mode state
+   */
+  static getNightMode(): boolean {
+    return (
+      (AsyncStorageManager.getBool(
+        AsyncStorageManager.PREFERENCES.nightMode.key,
+      ) &&
+        (!AsyncStorageManager.getBool(
+          AsyncStorageManager.PREFERENCES.nightModeFollowSystem.key,
+        ) ||
+          colorScheme === 'no-preference')) ||
+      (AsyncStorageManager.getBool(
+        AsyncStorageManager.PREFERENCES.nightModeFollowSystem.key,
+      ) &&
+        colorScheme === 'dark')
+    );
+  }
+
+  /**
+   * Get the current theme based on night mode and events
+   *
+   * @returns {ReactNativePaper.Theme} The current theme
+   */
+  static getCurrentTheme(): ReactNativePaper.Theme {
+    if (AprilFoolsManager.getInstance().isAprilFoolsEnabled()) {
+      return AprilFoolsManager.getAprilFoolsTheme(CustomWhiteTheme);
+    }
+    return ThemeManager.getBaseTheme();
+  }
+
+  /**
+   * Get the theme based on night mode
+   *
+   * @return {ReactNativePaper.Theme} The theme
+   */
+  static getBaseTheme(): ReactNativePaper.Theme {
+    if (ThemeManager.getNightMode()) {
+      return CustomDarkTheme;
+    }
+    return CustomWhiteTheme;
+  }
+
+  /**
+   * Sets the function to be called when the theme is changed (allows for general reload of the app)
+   *
+   * @param callback Function to call after theme change
+   */
+  setUpdateThemeCallback(callback: () => void) {
+    this.updateThemeCallback = callback;
+  }
+
+  /**
+   * Set night mode and save it to preferences
+   *
+   * @param isNightMode True to enable night mode, false to disable
+   */
+  setNightMode(isNightMode: boolean) {
+    AsyncStorageManager.set(
+      AsyncStorageManager.PREFERENCES.nightMode.key,
+      isNightMode,
+    );
+    if (this.updateThemeCallback != null) {
+      this.updateThemeCallback();
+    }
+  }
+}