add basic fingerprint auth on app launch

apps/mobile/App.js

@@ -1,4 +1,5 @@
 import React, {useEffect} from 'react';
+import {BackHandler} from 'react-native';
 import Orientation from 'react-native-orientation';
 import {SafeAreaProvider} from 'react-native-safe-area-context';
 import SplashScreen from 'react-native-splash-screen';
@@ -7,7 +8,9 @@ import {RootView} from './initializer.root';
 import AppLoader from './src/components/AppLoader';
 import {useTracked} from './src/provider';
 import {Actions} from './src/provider/Actions';
+import BiometricService from './src/services/BiometricService';
 import {DDS} from './src/services/DeviceDetection';
+import RNExitApp from 'react-native-exit-app';
 import {
   eSendEvent,
   eSubscribeEvent,
@@ -36,10 +39,28 @@ const App = () => {
               : 'mobile',
           });
         });
+
+        let func = async () => {
+          eSendEvent(eOpenSideMenu);
+          SplashScreen.hide();
+          await db.init();
+        };
+
         await SettingsService.init();
-        eSendEvent(eOpenSideMenu);
-        SplashScreen.hide();
-        await db.init();
+        if (SettingsService.get().appLockMode !== 'none') {
+          let result = await BiometricService.validateUser(
+            'Unlock to access your notes',
+            '',
+          );
+          if (result) {
+            await func();
+          } else {
+            RNExitApp.exitApp();
+            return;
+          }
+        } else {
+          await func();
+        }
       } catch (e) {
       } finally {
         initStatus = true;