diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index f7b0168..a5ac7ef 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -2,6 +2,9 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="de.k3b.android.lossless_jpg_crop">
 
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+
     <application
         android:name=".MainApp"
         android:allowBackup="true"
diff --git a/app/src/main/java/de/k3b/android/lossless_jpg_crop/BaseActivity.java b/app/src/main/java/de/k3b/android/lossless_jpg_crop/BaseActivity.java
new file mode 100644
index 0000000..19422aa
--- /dev/null
+++ b/app/src/main/java/de/k3b/android/lossless_jpg_crop/BaseActivity.java
@@ -0,0 +1,73 @@
+package de.k3b.android.lossless_jpg_crop;
+
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.DialogInterface;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.v4.app.ActivityCompat;
+
+/**
+ * Created by Oleksii Shliama (https://github.com/shliama).
+ */
+public class BaseActivity extends Activity {
+
+    private AlertDialog mAlertDialog;
+
+    /**
+     * Hide alert dialog if any.
+     */
+    @Override
+    protected void onStop() {
+        super.onStop();
+        if (mAlertDialog != null && mAlertDialog.isShowing()) {
+            mAlertDialog.dismiss();
+        }
+    }
+
+
+    /**
+     * Requests given permission.
+     * If the permission has been denied previously, a Dialog will prompt the user to grant the
+     * permission, otherwise it is requested directly.
+     */
+    protected void requestPermission(final String permission, String rationale, final int requestCode) {
+        if (ActivityCompat.shouldShowRequestPermissionRationale(this, permission)) {
+            showAlertDialog(getString(R.string.permission_title_rationale), rationale,
+                    new DialogInterface.OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            ActivityCompat.requestPermissions(BaseActivity.this,
+                                    new String[]{permission}, requestCode);
+                        }
+                    }, getString(android.R.string.ok), null, getString(android.R.string.cancel));
+        } else {
+            ActivityCompat.requestPermissions(this, new String[]{permission}, requestCode);
+        }
+    }
+
+    /**
+     * This method shows dialog with given title & message.
+     * Also there is an option to pass onClickListener for positive & negative button.
+     *
+     * @param title                         - dialog title
+     * @param message                       - dialog message
+     * @param onPositiveButtonClickListener - listener for positive button
+     * @param positiveText                  - positive button text
+     * @param onNegativeButtonClickListener - listener for negative button
+     * @param negativeText                  - negative button text
+     */
+    protected void showAlertDialog(@Nullable String title, @Nullable String message,
+                                   @Nullable DialogInterface.OnClickListener onPositiveButtonClickListener,
+                                   @NonNull String positiveText,
+                                   @Nullable DialogInterface.OnClickListener onNegativeButtonClickListener,
+                                   @NonNull String negativeText) {
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setTitle(title);
+        builder.setMessage(message);
+        builder.setPositiveButton(positiveText, onPositiveButtonClickListener);
+        builder.setNegativeButton(negativeText, onNegativeButtonClickListener);
+        mAlertDialog = builder.show();
+    }
+
+}
diff --git a/app/src/main/java/de/k3b/android/lossless_jpg_crop/MainActivity.java b/app/src/main/java/de/k3b/android/lossless_jpg_crop/MainActivity.java
index f37d247..e37d884 100644
--- a/app/src/main/java/de/k3b/android/lossless_jpg_crop/MainActivity.java
+++ b/app/src/main/java/de/k3b/android/lossless_jpg_crop/MainActivity.java
@@ -1,26 +1,30 @@
 package de.k3b.android.lossless_jpg_crop;
 
+import android.Manifest;
+import android.app.ActionBar;
 import android.content.Intent;
+import android.content.pm.PackageManager;
 import android.graphics.Color;
 import android.net.Uri;
+import android.os.Build;
 import android.support.annotation.NonNull;
-import android.support.v7.app.ActionBar;
-import android.support.v7.app.AppCompatActivity;
+import android.support.v4.app.ActivityCompat;
 import android.os.Bundle;
-import android.support.v7.widget.Toolbar;
 import android.util.Log;
 import android.widget.Toast;
 
-import com.yalantis.ucrop.UCrop;
-import com.yalantis.ucrop.UCropFragment;
-import com.yalantis.ucrop.UCropFragmentCallback;
+import com.yalantis.ucrop.view.GestureCropImageView;
+import com.yalantis.ucrop.view.OverlayView;
 import com.yalantis.ucrop.view.UCropView;
 
 import java.io.InputStream;
 import java.io.OutputStream;
 
-public class MainActivity extends AppCompatActivity  {
+public class MainActivity extends BaseActivity  {
     private static final String TAG = "ResultActivity";
+    private static final int REQUEST_GET_PICTURE = 1;
+    protected static final int REQUEST_GET_PICTURE_PERMISSION = 101;
+
 
     private ImageProcessor mSpectrum;
 
@@ -32,13 +36,25 @@ protected void onCreate(Bundle savedInstanceState) {
         mSpectrum = new ImageProcessor();
 
         Uri uri = getIntent().getData();
-        if (uri != null) {
+
+        if (uri == null) {
+            // must be called with image uri
+            pickFromGallery();
+        } else {
             try {
                 UCropView uCropView = findViewById(R.id.ucrop);
-                uCropView.getCropImageView().setImageUri(uri, null);
-                uCropView.getOverlayView().setShowCropFrame(false);
-                uCropView.getOverlayView().setShowCropGrid(false);
-                uCropView.getOverlayView().setDimmedColor(Color.TRANSPARENT);
+
+                final GestureCropImageView cropImageView = uCropView.getCropImageView();
+                cropImageView.setImageUri(uri, null);
+                cropImageView.setRotateEnabled(false);
+
+
+                final OverlayView cropOverlayView = uCropView.getOverlayView();
+                cropOverlayView.setShowCropFrame(true);
+                cropOverlayView.setShowCropGrid(true);
+                cropOverlayView.setDimmedColor(Color.TRANSPARENT);
+                cropOverlayView.setFreestyleCropMode(OverlayView.FREESTYLE_CROP_MODE_ENABLE);
+
 
                 /* parameters for UCropActivity/UCropFragment not used here
                 UCrop.Options options = new UCrop.Options();
@@ -63,8 +79,7 @@ protected void onCreate(Bundle savedInstanceState) {
         BitmapFactory.decodeFile(new File(getIntent().getData().getPath()).getAbsolutePath(), options);
         */
 
-        setSupportActionBar((Toolbar) findViewById(R.id.toolbar));
-        final ActionBar actionBar = getSupportActionBar();
+        final ActionBar actionBar = this.getActionBar();
         if (actionBar != null) {
             actionBar.setDisplayHomeAsUpEnabled(true);
             actionBar.setTitle(getString(R.string.app_name)); // , options.outWidth, options.outHeight));
@@ -72,8 +87,61 @@ protected void onCreate(Bundle savedInstanceState) {
 
     }
 
+    private void pickFromGallery() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN
+                && ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE)
+                != PackageManager.PERMISSION_GRANTED) {
+            requestPermission(Manifest.permission.READ_EXTERNAL_STORAGE,
+                    getString(R.string.permission_read_storage_rationale),
+                    REQUEST_GET_PICTURE_PERMISSION);
+        } else {
+            Intent intent = new Intent(Intent.ACTION_GET_CONTENT)
+                    .setType("image/jpeg")
+                    .addCategory(Intent.CATEGORY_OPENABLE);
+
+            startActivityForResult(Intent.createChooser(intent, getString(R.string.label_select_picture)), REQUEST_GET_PICTURE);
+        }
+    }
+    private void onGetPictureResult(int resultCode, Intent data) {
+        if (resultCode == RESULT_OK) {
+            final Uri selectedUri = data.getData();
+            if (selectedUri != null) {
+                Intent intent = new Intent(Intent.ACTION_VIEW, selectedUri, this, MainActivity.class);
+                this.startActivity(intent);
+                finish();
+                return;
+            }
+        }
+        Toast.makeText(this, R.string.toast_cannot_retrieve_selected_image, Toast.LENGTH_SHORT).show();
+        finish();
+        return;
+    }
+
+    /**
+     * Callback received when a permissions request has been completed.
+     */
+    @Override
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
+        switch (requestCode) {
+            case REQUEST_GET_PICTURE_PERMISSION:
+                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+                    pickFromGallery();
+                }
+                break;
+            default:
+                super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+        }
+    }
 
 
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent data) {
+        if (requestCode == REQUEST_GET_PICTURE) {
+            onGetPictureResult(resultCode, data);
+            return;
+        }
+        super.onActivityResult(requestCode, resultCode, data);
+    }
 
 
 
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index d5b881a..d053f0f 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -8,15 +8,6 @@
     tools:context=".MainActivity"
     >
 
-    <android.support.v7.widget.Toolbar
-        android:id="@+id/toolbar"
-        android:layout_width="match_parent"
-        android:layout_height="?attr/actionBarSize"
-        android:background="?colorAccent"
-        app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
-        app:title="@string/app_name"
-        app:titleTextColor="@android:color/white"/>
-
     <com.yalantis.ucrop.view.UCropView
         android:id="@+id/ucrop"
         android:layout_width="match_parent"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 364a84e..fcbf428 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,3 +1,14 @@
 <resources>
     <string name="app_name">Loss-Less-Crop</string>
+
+    <string name="label_select_picture">Select Picture</string>
+
+    <string name="permission_title_rationale">Permission needed</string>
+    <string name="permission_read_storage_rationale">Storage read permission is needed to pick files.</string>
+    <string name="permission_write_storage_rationale">Storage write permission is needed to save the image.</string>
+
+    <string name="toast_cannot_retrieve_selected_image">Cannot retrieve selected image</string>
+    <string name="toast_cannot_retrieve_cropped_image">Cannot retrieve cropped image</string>
+    <string name="toast_unexpected_error">Unexpected error</string>
+
 </resources>
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 5885930..f927816 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -1,7 +1,7 @@
 <resources>
 
     <!-- Base application theme. -->
-    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
+    <style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">
         <!-- Customize your theme here. -->
         <item name="colorPrimary">@color/colorPrimary</item>
         <item name="colorPrimaryDark">@color/colorPrimaryDark</item>