diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 2147dc33..cf09287e 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -8,6 +8,7 @@
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
 
     <application
+        android:name=".AegisApplication"
         android:allowBackup="true"
         android:icon="@mipmap/icon"
         android:label="@string/app_name"
diff --git a/app/src/main/java/me/impy/aegis/AddProfileActivity.java b/app/src/main/java/me/impy/aegis/AddProfileActivity.java
index 28770c96..24efcb46 100644
--- a/app/src/main/java/me/impy/aegis/AddProfileActivity.java
+++ b/app/src/main/java/me/impy/aegis/AddProfileActivity.java
@@ -2,8 +2,6 @@ package me.impy.aegis;
 
 import android.app.Activity;
 import android.content.Intent;
-import android.content.SharedPreferences;
-import android.preference.PreferenceManager;
 import android.support.design.widget.FloatingActionButton;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
@@ -15,18 +13,21 @@ import android.widget.TextView;
 import me.impy.aegis.crypto.KeyInfo;
 
 public class AddProfileActivity extends AppCompatActivity {
+    private KeyProfile _keyProfile;
 
-    KeyProfile _keyProfile;
+    private EditText _profileName;
+    private TextView _textAlgorithm;
+    private TextView _textIssuer;
+    private TextView _textPeriod;
+    private TextView _textOtp;
 
-    EditText _profileName;
-    TextView _textAlgorithm;
-    TextView _textIssuer;
-    TextView _textPeriod;
-    TextView _textOtp;
+    private AegisApplication _app;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        _app = (AegisApplication) getApplication();
+
         setPreferredTheme();
         setContentView(R.layout.activity_add_profile);
 
@@ -82,8 +83,7 @@ public class AddProfileActivity extends AppCompatActivity {
     }
 
     private void setPreferredTheme() {
-        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
-        if (sharedPreferences.getBoolean("pref_night_mode", false)) {
+        if (_app.getPreferences().getBoolean("pref_night_mode", false)) {
             setTheme(R.style.AppTheme_Dark_TransparentActionBar);
         } else {
             setTheme(R.style.AppTheme_Default_TransparentActionBar);
diff --git a/app/src/main/java/me/impy/aegis/AegisApplication.java b/app/src/main/java/me/impy/aegis/AegisApplication.java
new file mode 100644
index 00000000..7c00d6f0
--- /dev/null
+++ b/app/src/main/java/me/impy/aegis/AegisApplication.java
@@ -0,0 +1,34 @@
+package me.impy.aegis;
+
+import android.app.Application;
+import android.content.SharedPreferences;
+import android.preference.PreferenceManager;
+
+import me.impy.aegis.db.DatabaseManager;
+
+public class AegisApplication extends Application {
+    private boolean _running = false;
+    private DatabaseManager _manager = new DatabaseManager(this);
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+    }
+
+    public DatabaseManager getDatabaseManager() {
+        return _manager;
+    }
+
+    public SharedPreferences getPreferences() {
+        return PreferenceManager.getDefaultSharedPreferences(this);
+    }
+
+    public boolean isRunning() {
+        // return false the first time this is called
+        if (_running) {
+            return true;
+        }
+        _running = true;
+        return false;
+    }
+}
diff --git a/app/src/main/java/me/impy/aegis/AuthActivity.java b/app/src/main/java/me/impy/aegis/AuthActivity.java
index a49202cb..c1428b1c 100644
--- a/app/src/main/java/me/impy/aegis/AuthActivity.java
+++ b/app/src/main/java/me/impy/aegis/AuthActivity.java
@@ -1,6 +1,5 @@
 package me.impy.aegis;
 
-import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.hardware.fingerprint.FingerprintManager;
diff --git a/app/src/main/java/me/impy/aegis/CustomAuthenticationSlide.java b/app/src/main/java/me/impy/aegis/CustomAuthenticationSlide.java
index 43ce89b8..2cd5d397 100644
--- a/app/src/main/java/me/impy/aegis/CustomAuthenticationSlide.java
+++ b/app/src/main/java/me/impy/aegis/CustomAuthenticationSlide.java
@@ -1,6 +1,5 @@
 package me.impy.aegis;
 
-import android.content.Context;
 import android.content.Intent;
 import android.hardware.fingerprint.FingerprintManager;
 import android.os.Bundle;
diff --git a/app/src/main/java/me/impy/aegis/IntroActivity.java b/app/src/main/java/me/impy/aegis/IntroActivity.java
index a1977ceb..115fc5a9 100644
--- a/app/src/main/java/me/impy/aegis/IntroActivity.java
+++ b/app/src/main/java/me/impy/aegis/IntroActivity.java
@@ -1,9 +1,7 @@
 package me.impy.aegis;
 
 import android.Manifest;
-import android.content.Context;
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.support.v4.app.Fragment;
 
@@ -37,9 +35,13 @@ public class IntroActivity extends AppIntro implements DerivationTask.Callback {
     private PasswordSlot _passwordSlot;
     private Cipher _passwordCipher;
 
+    private AegisApplication _app;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        _app = (AegisApplication) getApplication();
+
         showSkipButton(false);
         //showPagerIndicator(false);
         setGoBackLock(true);
@@ -189,8 +191,7 @@ public class IntroActivity extends AppIntro implements DerivationTask.Callback {
         setResult(RESULT_OK, result);
 
         // skip the intro from now on
-        SharedPreferences prefs = this.getSharedPreferences("me.impy.aegis", Context.MODE_PRIVATE);
-        prefs.edit().putBoolean("passedIntro", true).apply();
+        _app.getPreferences().edit().putBoolean("pref_intro", true).apply();
         finish();
     }
 
diff --git a/app/src/main/java/me/impy/aegis/KeyProfileAdapter.java b/app/src/main/java/me/impy/aegis/KeyProfileAdapter.java
index e7b05e1d..d50001bb 100644
--- a/app/src/main/java/me/impy/aegis/KeyProfileAdapter.java
+++ b/app/src/main/java/me/impy/aegis/KeyProfileAdapter.java
@@ -13,10 +13,16 @@ import me.impy.aegis.helpers.ItemTouchHelperAdapter;
 public class KeyProfileAdapter extends RecyclerView.Adapter<KeyProfileHolder> implements ItemTouchHelperAdapter {
     private ArrayList<KeyProfile> _keyProfiles;
     private static Listener _listener;
+    private boolean _showIssuer;
 
-    public KeyProfileAdapter(Listener listener) {
+    public KeyProfileAdapter(Listener listener, boolean showIssuer) {
         _keyProfiles = new ArrayList<>();
         _listener = listener;
+        _showIssuer = showIssuer;
+    }
+
+    public void setShowIssuer(boolean showIssuer) {
+        _showIssuer = showIssuer;
     }
 
     public void addKey(KeyProfile profile) {
@@ -36,6 +42,11 @@ public class KeyProfileAdapter extends RecyclerView.Adapter<KeyProfileHolder> im
         notifyItemRemoved(position);
     }
 
+    public void clearKeys() {
+        _keyProfiles.clear();
+        notifyDataSetChanged();
+    }
+
     @Override
     public void onItemDismiss(int position) {
 
@@ -64,14 +75,14 @@ public class KeyProfileAdapter extends RecyclerView.Adapter<KeyProfileHolder> im
 
     @Override
     public void onViewRecycled(KeyProfileHolder holder) {
-        holder.setData(null);
+        holder.setData(null, _showIssuer);
         super.onViewRecycled(holder);
     }
 
     @Override
     public void onBindViewHolder(final KeyProfileHolder holder, int position) {
         final KeyProfile profile = _keyProfiles.get(position);
-        holder.setData(profile);
+        holder.setData(profile, _showIssuer);
         holder.startUpdateLoop();
         holder.itemView.setOnClickListener(new View.OnClickListener() {
             @Override
diff --git a/app/src/main/java/me/impy/aegis/KeyProfileHolder.java b/app/src/main/java/me/impy/aegis/KeyProfileHolder.java
index 7121037b..39aac446 100644
--- a/app/src/main/java/me/impy/aegis/KeyProfileHolder.java
+++ b/app/src/main/java/me/impy/aegis/KeyProfileHolder.java
@@ -1,9 +1,7 @@
 package me.impy.aegis;
 
 import android.animation.ObjectAnimator;
-import android.content.SharedPreferences;
 import android.os.Handler;
-import android.preference.PreferenceManager;
 import android.support.v7.widget.RecyclerView;
 import android.view.View;
 import android.view.animation.LinearInterpolator;
@@ -21,23 +19,21 @@ public class KeyProfileHolder extends RecyclerView.ViewHolder {
     private ImageView _profileDrawable;
     private KeyProfile _keyProfile;
     private ProgressBar _progressBar;
-    private View _itemView;
 
     private Handler _uiHandler;
     private boolean _running = false;
 
-    KeyProfileHolder(final View itemView) {
-        super(itemView);
-        _itemView = itemView;
-        _profileName = itemView.findViewById(R.id.profile_name);
-        _profileCode = itemView.findViewById(R.id.profile_code);
-        _profileIssuer = itemView.findViewById(R.id.profile_issuer);
-        _profileDrawable = itemView.findViewById(R.id.ivTextDrawable);
-        _progressBar = itemView.findViewById(R.id.progressBar);
+    KeyProfileHolder(final View view) {
+        super(view);
+        _profileName = view.findViewById(R.id.profile_name);
+        _profileCode = view.findViewById(R.id.profile_code);
+        _profileIssuer = view.findViewById(R.id.profile_issuer);
+        _profileDrawable = view.findViewById(R.id.ivTextDrawable);
+        _progressBar = view.findViewById(R.id.progressBar);
         _uiHandler = new Handler();
     }
 
-    public void setData(KeyProfile profile) {
+    public void setData(KeyProfile profile, boolean showIssuer) {
         if ((_keyProfile = profile) == null) {
             _running = false;
             return;
@@ -46,9 +42,7 @@ public class KeyProfileHolder extends RecyclerView.ViewHolder {
         _profileName.setText(profile.getEntry().getName());
         _profileCode.setText(profile.getCode());
         _profileIssuer.setText("");
-
-        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(_itemView.getContext());
-        if (sharedPreferences.getBoolean("pref_issuer", false)) {
+        if (showIssuer) {
             _profileIssuer.setText(" - " + profile.getEntry().getInfo().getIssuer());
         }
 
diff --git a/app/src/main/java/me/impy/aegis/MainActivity.java b/app/src/main/java/me/impy/aegis/MainActivity.java
index 3313eb26..79122daa 100644
--- a/app/src/main/java/me/impy/aegis/MainActivity.java
+++ b/app/src/main/java/me/impy/aegis/MainActivity.java
@@ -6,13 +6,11 @@ import android.content.ClipboardManager;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.content.pm.ShortcutInfo;
 import android.content.pm.ShortcutManager;
 import android.graphics.drawable.Icon;
 import android.media.MediaScannerConnection;
 import android.os.Build;
-import android.preference.PreferenceManager;
 import android.support.design.widget.BottomSheetDialog;
 import android.support.design.widget.FloatingActionButton;
 import android.support.v7.app.AlertDialog;
@@ -58,6 +56,7 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
     private static final int CODE_PERM_CAMERA = 2;
 
     private KeyProfileAdapter _keyProfileAdapter;
+    private AegisApplication _app;
     private DatabaseManager _db;
 
     private boolean _nightMode = false;
@@ -66,40 +65,18 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        _db = new DatabaseManager(getApplicationContext());
+        _app = (AegisApplication) getApplication();
+        _db = _app.getDatabaseManager();
 
-        SharedPreferences prefs = this.getSharedPreferences("me.impy.aegis", Context.MODE_PRIVATE);
-        if (!prefs.getBoolean("passedIntro", false)) {
-            Intent intro = new Intent(this, IntroActivity.class);
-            startActivityForResult(intro, CODE_DO_INTRO);
-        } else {
-            try {
-                _db.load();
-                if (!_db.isDecrypted()) {
-                    Intent intent = new Intent(this, AuthActivity.class);
-                    intent.putExtra("slots", _db.getFile().getSlots());
-                    startActivityForResult(intent, CODE_DECRYPT);
-                }
-            } catch (FileNotFoundException e) {
-                // start the intro if the db file was not found
-                Toast.makeText(this, "Database file not found, starting over...", Toast.LENGTH_SHORT).show();
-                Intent intro = new Intent(this, IntroActivity.class);
-                startActivityForResult(intro, CODE_DO_INTRO);
-            } catch (Exception e) {
-                e.printStackTrace();
-                Toast.makeText(this, "An error occurred while trying to deserialize the database", Toast.LENGTH_LONG).show();
-                throw new UndeclaredThrowableException(e);
-            }
-        }
-
-        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
-        if (sharedPreferences.getBoolean("pref_night_mode", false)) {
+        // set the theme
+        if (_app.getPreferences().getBoolean("pref_night_mode", false)) {
             _nightMode = true;
             setTheme(R.style.AppTheme_Dark_NoActionBar);
         } else {
             setPreferredTheme();
         }
 
+        // set up the main view
         setContentView(R.layout.activity_main);
         Toolbar toolbar = findViewById(R.id.toolbar);
         setSupportActionBar(toolbar);
@@ -108,25 +85,49 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
         initializeAppShortcuts();
         doShortcutActions();
 
+        // set up the floating action button
         FloatingActionButton fab = findViewById(R.id.fab);
         fab.setEnabled(true);
-        fab.setOnClickListener(view -> {
-            onGetKeyInfo();
-        });
+        fab.setOnClickListener(view -> onGetKeyInfo());
 
+        // set up the recycler view for the key profiles
+        _keyProfileAdapter = new KeyProfileAdapter(this, _app.getPreferences().getBoolean("pref_issuer", false));
         RecyclerView rvKeyProfiles = findViewById(R.id.rvKeyProfiles);
         LinearLayoutManager mLayoutManager = new LinearLayoutManager(this);
         rvKeyProfiles.setLayoutManager(mLayoutManager);
-
-        _keyProfileAdapter = new KeyProfileAdapter(this);
-        if (_db.isDecrypted()) {
-            loadKeyProfiles();
-        }
-
         ItemTouchHelper.Callback callback = new SimpleItemTouchHelperCallback(_keyProfileAdapter);
         ItemTouchHelper touchHelper = new ItemTouchHelper(callback);
         touchHelper.attachToRecyclerView(rvKeyProfiles);
         rvKeyProfiles.setAdapter(_keyProfileAdapter);
+
+        if (!_app.isRunning() && !_db.isUnlocked()) {
+            if (!_app.getPreferences().getBoolean("pref_intro", false)) {
+                Intent intro = new Intent(this, IntroActivity.class);
+                startActivityForResult(intro, CODE_DO_INTRO);
+            } else {
+                try {
+                    _db.load();
+                    if (!_db.isUnlocked()) {
+                        Intent intent = new Intent(this, AuthActivity.class);
+                        intent.putExtra("slots", _db.getFile().getSlots());
+                        startActivityForResult(intent, CODE_DECRYPT);
+                    }
+                } catch (FileNotFoundException e) {
+                    // start the intro if the db file was not found
+                    Toast.makeText(this, "Database file not found, starting over...", Toast.LENGTH_SHORT).show();
+                    Intent intro = new Intent(this, IntroActivity.class);
+                    startActivityForResult(intro, CODE_DO_INTRO);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                    Toast.makeText(this, "An error occurred while trying to deserialize the database", Toast.LENGTH_LONG).show();
+                    throw new UndeclaredThrowableException(e);
+                }
+            }
+        }
+
+        if (_db.isUnlocked()) {
+            loadKeyProfiles();
+        }
     }
 
     @Override
@@ -176,6 +177,8 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
     private void onPreferencesResult(int resultCode, Intent data) {
         // refresh the entire key profile list if needed
         if (data.getBooleanExtra("needsRefresh", false)) {
+            boolean showIssuer = _app.getPreferences().getBoolean("pref_issuer", false);
+            _keyProfileAdapter.setShowIssuer(showIssuer);
             _keyProfileAdapter.notifyDataSetChanged();
         }
 
@@ -344,8 +347,8 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
         MasterKey key = (MasterKey) data.getSerializableExtra("key");
         try {
             _db.load();
-            if (!_db.isDecrypted()) {
-                _db.setMasterKey(key);
+            if (!_db.isUnlocked()) {
+                _db.unlock(key);
             }
         } catch (Exception e) {
             e.printStackTrace();
@@ -360,7 +363,7 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
     private void onDecryptResult(int resultCode, Intent data) {
         MasterKey key = (MasterKey) data.getSerializableExtra("key");
         try {
-            _db.setMasterKey(key);
+            _db.unlock(key);
         } catch (Exception e) {
             e.printStackTrace();
             Toast.makeText(this, "An error occurred while trying to decrypt the database", Toast.LENGTH_LONG).show();
@@ -375,7 +378,7 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
     private void doShortcutActions() {
         Intent intent = getIntent();
         String mode = intent.getStringExtra("Action");
-        if (mode == null || !_db.isDecrypted()) {
+        if (mode == null || !_db.isUnlocked()) {
             return;
         }
 
@@ -475,8 +478,16 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
                 }
                 return true;
             case R.id.action_lock:
-                // TODO: properly close the database
-                recreate();
+                _keyProfileAdapter.clearKeys();
+                try {
+                    _db.lock();
+                } catch (Exception e) {
+                    e.printStackTrace();
+                    Toast.makeText(this, "An error occurred while trying to lock the database", Toast.LENGTH_LONG).show();
+                }
+                Intent intent = new Intent(this, AuthActivity.class);
+                intent.putExtra("slots", _db.getFile().getSlots());
+                startActivityForResult(intent, CODE_DECRYPT);
                 return true;
             default:
                 return super.onOptionsItemSelected(item);
@@ -514,8 +525,7 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
 
     private void setPreferredTheme() {
         boolean restart = false;
-        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
-        if (sharedPreferences.getBoolean("pref_night_mode", false)) {
+        if (_app.getPreferences().getBoolean("pref_night_mode", false)) {
             if (!_nightMode) {
                 setTheme(R.style.AppTheme_Dark_NoActionBar);
                 restart = true;
@@ -555,7 +565,7 @@ public class MainActivity extends AppCompatActivity implements KeyProfileAdapter
 
     private void updateLockIcon() {
         // hide the lock icon if the database is not encrypted
-        if (_menu != null && _db.isDecrypted()) {
+        if (_menu != null && _db.isUnlocked()) {
             MenuItem item = _menu.findItem(R.id.action_lock);
             item.setVisible(_db.getFile().isEncrypted());
         }
diff --git a/app/src/main/java/me/impy/aegis/PreferencesActivity.java b/app/src/main/java/me/impy/aegis/PreferencesActivity.java
index fa7fde1e..6293e3f9 100644
--- a/app/src/main/java/me/impy/aegis/PreferencesActivity.java
+++ b/app/src/main/java/me/impy/aegis/PreferencesActivity.java
@@ -1,23 +1,23 @@
 package me.impy.aegis;
 
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.preference.Preference;
 import android.preference.PreferenceFragment;
-import android.preference.PreferenceManager;
 import android.support.v7.app.AppCompatActivity;
 import android.widget.Toast;
 
 public class PreferencesActivity extends AppCompatActivity {
     public static final int ACTION_EXPORT = 0;
 
+    private AegisApplication _app;
+
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        _app = (AegisApplication) getApplication();
 
-        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
-        if (preferences.getBoolean("pref_night_mode", false)) {
+        if (_app.getPreferences().getBoolean("pref_night_mode", false)) {
             setTheme(R.style.AppTheme_Dark);
         } else {
             setTheme(R.style.AppTheme_Default);
diff --git a/app/src/main/java/me/impy/aegis/db/DatabaseManager.java b/app/src/main/java/me/impy/aegis/db/DatabaseManager.java
index b05c4fd6..85f7e7d0 100644
--- a/app/src/main/java/me/impy/aegis/db/DatabaseManager.java
+++ b/app/src/main/java/me/impy/aegis/db/DatabaseManager.java
@@ -57,7 +57,14 @@ public class DatabaseManager {
         }
     }
 
-    public void setMasterKey(MasterKey key) throws Exception {
+    public void lock() throws Exception {
+        assertUnlocked();
+        // TODO: properly clear everything
+        _key = null;
+        _db = null;
+    }
+
+    public void unlock(MasterKey key) throws Exception {
         assertLoaded();
         byte[] encrypted = _file.getContent();
         CryptParameters params = _file.getCryptParameters();
@@ -83,7 +90,7 @@ public class DatabaseManager {
     }
 
     public void save() throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         byte[] dbBytes = _db.serialize();
         if (!_file.isEncrypted()) {
             _file.setContent(dbBytes);
@@ -96,7 +103,7 @@ public class DatabaseManager {
     }
 
     public String export(boolean encrypt) throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         byte[] bytes = _db.serialize();
         encrypt = encrypt && getFile().isEncrypted();
         if (encrypt) {
@@ -129,22 +136,22 @@ public class DatabaseManager {
     }
 
     public void addKey(DatabaseEntry entry) throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         _db.addKey(entry);
     }
 
     public void removeKey(DatabaseEntry entry) throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         _db.removeKey(entry);
     }
 
     public void swapKeys(DatabaseEntry entry1, DatabaseEntry entry2) throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         _db.swapKeys(entry1, entry2);
     }
 
     public List<DatabaseEntry> getKeys() throws Exception {
-        assertDecrypted();
+        assertUnlocked();
         return _db.getKeys();
     }
 
@@ -156,7 +163,7 @@ public class DatabaseManager {
         return _file != null;
     }
 
-    public boolean isDecrypted() {
+    public boolean isUnlocked() {
         return _db != null;
     }
 
@@ -166,10 +173,10 @@ public class DatabaseManager {
         }
     }
 
-    private void assertDecrypted() throws Exception {
+    private void assertUnlocked() throws Exception {
         assertLoaded();
-        if (!isDecrypted()) {
-            throw new Exception("database file has not been decrypted yet");
+        if (!isUnlocked()) {
+            throw new Exception("database file has not been unlocked yet");
         }
     }
 }