diff --git a/app/src/main/java/me/impy/aegis/AuthActivity.java b/app/src/main/java/me/impy/aegis/AuthActivity.java
index da629e28..eee62946 100644
--- a/app/src/main/java/me/impy/aegis/AuthActivity.java
+++ b/app/src/main/java/me/impy/aegis/AuthActivity.java
@@ -35,7 +35,7 @@ import me.impy.aegis.crypto.slots.SlotIntegrityException;
 import me.impy.aegis.finger.FingerprintUiHelper;
 import me.impy.aegis.helpers.AuthHelper;
 
-public class AuthActivity extends AppCompatActivity implements FingerprintUiHelper.Callback {
+public class AuthActivity extends AppCompatActivity implements FingerprintUiHelper.Callback, SlotCollectionTask.Callback {
     public static final int RESULT_OK = 0;
     public static final int RESULT_EXCEPTION = 1;
 
@@ -82,7 +82,8 @@ public class AuthActivity extends AppCompatActivity implements FingerprintUiHelp
         button.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
-                trySlots(PasswordSlot.class);
+                char[] password = AuthHelper.getPassword(_textPassword, true);
+                trySlots(PasswordSlot.class, password);
             }
         });
     }
@@ -100,48 +101,19 @@ public class AuthActivity extends AppCompatActivity implements FingerprintUiHelp
         builder.create().show();
     }
 
-    private MasterKey decryptPasswordSlot(PasswordSlot slot) throws Exception {
-        char[] password = AuthHelper.getPassword(_textPassword, true);
-        SecretKey key = slot.deriveKey(password);
-        CryptoUtils.zero(password);
-        Cipher cipher = Slot.createCipher(key, Cipher.DECRYPT_MODE);
-        return _slots.decrypt(slot, cipher);
-    }
+    /*DerivationTask task = new DerivationTask(this);
+    DerivationTask.Params params = new DerivationTask.Params() {{
+        Slots = _slots;
+        Slot = (PasswordSlot) slot;
+        Password = AuthHelper.getPassword(_textPassword, true);
+    }};
+    masterKey = task.execute(params).get();*/
 
-    private MasterKey decryptFingerSlot(FingerprintSlot slot) throws Exception {
-        return _slots.decrypt(slot, _fingerCipher);
-    }
-
-    private <T extends Slot> void trySlots(Class<T> type) {
-        try {
-            if (!_slots.has(type)) {
-                throw new RuntimeException();
-            }
-
-            MasterKey masterKey = null;
-            for (Slot slot : _slots.findAll(type)) {
-                try {
-                    if (slot instanceof PasswordSlot) {
-                        masterKey = decryptPasswordSlot((PasswordSlot) slot);
-                    } else if (slot instanceof FingerprintSlot) {
-                        masterKey = decryptFingerSlot((FingerprintSlot) slot);
-                    } else {
-                        throw new RuntimeException();
-                    }
-                    break;
-                } catch (SlotIntegrityException e) { }
-            }
-
-            if (masterKey == null) {
-                throw new SlotIntegrityException();
-            }
-
-            setKey(masterKey);
-        } catch (SlotIntegrityException e) {
-            showError();
-        } catch (Exception e) {
-            throw new UndeclaredThrowableException(e);
-        }
+    private <T extends Slot> void trySlots(Class<T> type, Object obj) {
+        new SlotCollectionTask<T>(type, this, this).execute(new SlotCollectionTask.Params(){{
+            Slots = _slots;
+            Obj = obj;
+        }});
     }
 
     private void setKey(MasterKey key) {
@@ -177,11 +149,20 @@ public class AuthActivity extends AppCompatActivity implements FingerprintUiHelp
 
     @Override
     public void onAuthenticated() {
-        trySlots(FingerprintSlot.class);
+        trySlots(FingerprintSlot.class, _fingerCipher);
     }
 
     @Override
     public void onError() {
 
     }
+
+    @Override
+    public void onTaskFinished(MasterKey key) {
+        if (key != null) {
+            setKey(key);
+        } else {
+            showError();
+        }
+    }
 }
diff --git a/app/src/main/java/me/impy/aegis/MainActivity.java b/app/src/main/java/me/impy/aegis/MainActivity.java
index 79f58947..e6a560b2 100644
--- a/app/src/main/java/me/impy/aegis/MainActivity.java
+++ b/app/src/main/java/me/impy/aegis/MainActivity.java
@@ -32,7 +32,6 @@ import java.lang.reflect.UndeclaredThrowableException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.Comparator;
 import java.util.Objects;
 
 import me.impy.aegis.crypto.MasterKey;
diff --git a/app/src/main/java/me/impy/aegis/SlotCollectionTask.java b/app/src/main/java/me/impy/aegis/SlotCollectionTask.java
new file mode 100644
index 00000000..7b9ddd18
--- /dev/null
+++ b/app/src/main/java/me/impy/aegis/SlotCollectionTask.java
@@ -0,0 +1,91 @@
+package me.impy.aegis;
+
+import android.app.ProgressDialog;
+import android.content.Context;
+import android.os.AsyncTask;
+
+import java.lang.reflect.UndeclaredThrowableException;
+
+import javax.crypto.Cipher;
+import javax.crypto.SecretKey;
+
+import me.impy.aegis.crypto.CryptoUtils;
+import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.crypto.slots.FingerprintSlot;
+import me.impy.aegis.crypto.slots.PasswordSlot;
+import me.impy.aegis.crypto.slots.Slot;
+import me.impy.aegis.crypto.slots.SlotCollection;
+import me.impy.aegis.crypto.slots.SlotIntegrityException;
+
+public class SlotCollectionTask<T extends Slot> extends AsyncTask<SlotCollectionTask.Params, Void, MasterKey> {
+    private Callback _cb;
+    private Class<T> _type;
+    private ProgressDialog _dialog;
+
+    public SlotCollectionTask(Class<T> type, Context context, Callback cb) {
+        _cb = cb;
+        _type = type;
+        _dialog = new ProgressDialog(context);
+    }
+
+    @Override
+    protected MasterKey doInBackground(SlotCollectionTask.Params... args) {
+        SlotCollectionTask.Params params = args[0];
+        try {
+            if (!params.Slots.has(_type)) {
+                throw new RuntimeException();
+            }
+
+            MasterKey masterKey = null;
+            for (Slot slot : params.Slots.findAll(_type)) {
+                try {
+                    if (slot instanceof PasswordSlot) {
+                        char[] password = (char[])params.Obj;
+                        SecretKey key = ((PasswordSlot)slot).deriveKey(password);
+                        CryptoUtils.zero(password);
+                        Cipher cipher = Slot.createCipher(key, Cipher.DECRYPT_MODE);
+                        masterKey = params.Slots.decrypt(slot, cipher);
+                    } else if (slot instanceof FingerprintSlot) {
+                        masterKey = params.Slots.decrypt(slot, (Cipher)params.Obj);
+                    } else {
+                        throw new RuntimeException();
+                    }
+                    break;
+                } catch (SlotIntegrityException e) { }
+            }
+
+            if (masterKey == null) {
+                throw new SlotIntegrityException();
+            }
+
+            return masterKey;
+        } catch (SlotIntegrityException e) {
+            return null;
+        } catch (Exception e) {
+            throw new UndeclaredThrowableException(e);
+        }
+    }
+
+    @Override
+    protected void onPreExecute() {
+        _dialog.setMessage("Decrypting database");
+        _dialog.show();
+    }
+
+    @Override
+    protected void onPostExecute(MasterKey masterKey) {
+        if (_dialog.isShowing()) {
+            _dialog.dismiss();
+        }
+        _cb.onTaskFinished(masterKey);
+    }
+
+    static class Params {
+        public SlotCollection Slots;
+        public Object Obj;
+    }
+
+    interface Callback {
+        void onTaskFinished(MasterKey key);
+    }
+}