diff --git a/native/android/Android.mk b/native/android/Android.mk
index cc35a3a..44ec83f 100644
--- a/native/android/Android.mk
+++ b/native/android/Android.mk
@@ -12,6 +12,7 @@
     looper.cpp \
     native_activity.cpp \
     native_window.cpp \
+    obb.cpp \
     sensor.cpp \
     storage_manager.cpp
 
diff --git a/native/android/obb.cpp b/native/android/obb.cpp
new file mode 100644
index 0000000..e0cb1a6
--- /dev/null
+++ b/native/android/obb.cpp
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "NObb"
+
+#include <android/obb.h>
+
+#include <utils/Log.h>
+#include <utils/ObbFile.h>
+
+using namespace android;
+
+struct AObbInfo : public ObbFile {};
+
+AObbInfo* AObbScanner_getObbInfo(const char* filename) {
+    AObbInfo* obbFile = new AObbInfo();
+    if (obbFile == NULL || !obbFile->readFrom(filename)) {
+        delete obbFile;
+        return NULL;
+    }
+    obbFile->incStrong((void*)AObbScanner_getObbInfo);
+    return static_cast<AObbInfo*>(obbFile);
+}
+
+void AObbInfo_delete(AObbInfo* obbInfo) {
+    if (obbInfo != NULL) {
+        obbInfo->decStrong((void*)AObbScanner_getObbInfo);
+    }
+}
+
+const char* AObbInfo_getPackageName(AObbInfo* obbInfo) {
+    return obbInfo->getPackageName();
+}
+
+int32_t AObbInfo_getVersion(AObbInfo* obbInfo) {
+    return obbInfo->getVersion();
+}
+
+int32_t AObbInfo_getFlags(AObbInfo* obbInfo) {
+    return obbInfo->getFlags();
+}
diff --git a/native/android/storage_manager.cpp b/native/android/storage_manager.cpp
index 6dbe746..2f20641 100644
--- a/native/android/storage_manager.cpp
+++ b/native/android/storage_manager.cpp
@@ -38,20 +38,20 @@
             mStorageManager(mgr)
     {}
 
-    virtual void onObbResult(const android::String16& filename, const android::String16& state) {
-        LOGD("Got obb result (%s, %s)\n", String8(filename).string(), String8(state).string());
-    }
+    virtual void onObbResult(const android::String16& filename, const android::String16& state);
 };
 
 struct AStorageManager : public RefBase {
 protected:
-    void* mObbCallback;
+    AStorageManager_obbCallbackFunc mObbCallback;
+    void* mObbCallbackData;
     sp<ObbActionListener> mObbActionListener;
     sp<IMountService> mMountService;
 
 public:
-    AStorageManager() :
-            mObbCallback(NULL)
+    AStorageManager()
+            : mObbCallback(NULL)
+            , mObbCallbackData(NULL)
     {
     }
 
@@ -73,8 +73,15 @@
         return true;
     }
 
-    void setObbCallback(void* cb) {
+    void setObbCallback(AStorageManager_obbCallbackFunc cb, void* data) {
         mObbCallback = cb;
+        mObbCallbackData = data;
+    }
+
+    void fireCallback(const char* filename, const char* state) {
+        if (mObbCallback != NULL) {
+            mObbCallback(filename, state, mObbCallbackData);
+        }
     }
 
     void mountObb(const char* filename, const char* key) {
@@ -85,7 +92,7 @@
 
     void unmountObb(const char* filename, const bool force) {
         String16 filename16(filename);
-        mMountService->unmountObb(filename16, force);
+        mMountService->unmountObb(filename16, force, mObbActionListener);
     }
 
     int isObbMounted(const char* filename) {
@@ -104,6 +111,10 @@
     }
 };
 
+void ObbActionListener::onObbResult(const android::String16& filename, const android::String16& state) {
+    mStorageManager->fireCallback(String8(filename).string(), String8(state).string());
+}
+
 
 AStorageManager* AStorageManager_new() {
     sp<AStorageManager> mgr = new AStorageManager();
@@ -120,8 +131,8 @@
     }
 }
 
-void AStorageManager_setObbCallback(AStorageManager* mgr, void* cb) {
-    mgr->setObbCallback(cb);
+void AStorageManager_setObbCallback(AStorageManager* mgr, AStorageManager_obbCallbackFunc cb, void* data) {
+    mgr->setObbCallback(cb, data);
 }
 
 void AStorageManager_mountObb(AStorageManager* mgr, const char* filename, const char* key) {
diff --git a/native/include/android/obb.h b/native/include/android/obb.h
new file mode 100644
index 0000000..65e9b2a
--- /dev/null
+++ b/native/include/android/obb.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+#ifndef ANDROID_OBB_H
+#define ANDROID_OBB_H
+
+#include <sys/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct AObbInfo;
+typedef struct AObbInfo AObbInfo;
+
+enum {
+    AOBBINFO_OVERLAY = 0x0001,
+};
+
+/**
+ * Scan an OBB and get information about it.
+ */
+AObbInfo* AObbScanner_getObbInfo(const char* filename);
+
+/**
+ * Destroy the AObbInfo object. You must call this when finished with the object.
+ */
+void AObbInfo_delete(AObbInfo* obbInfo);
+
+/**
+ * Get the package name for the OBB.
+ */
+const char* AObbInfo_getPackageName(AObbInfo* obbInfo);
+
+/**
+ * Get the version of an OBB file.
+ */
+int32_t AObbInfo_getVersion(AObbInfo* obbInfo);
+
+/**
+ * Get the flags of an OBB file.
+ */
+int32_t AObbInfo_getFlags(AObbInfo* obbInfo);
+
+#ifdef __cplusplus
+};
+#endif
+
+#endif      // ANDROID_OBB_H
diff --git a/native/include/android/storage_manager.h b/native/include/android/storage_manager.h
index bbed8a4..6f925c1 100644
--- a/native/include/android/storage_manager.h
+++ b/native/include/android/storage_manager.h
@@ -37,17 +37,22 @@
 void AStorageManager_delete(AStorageManager* mgr);
 
 /**
- * Callback to call when requested OBB is complete.
+ * Callback function for asynchronous calls made on OBB files.
  */
-void AStorageManager_setObbCallback(AStorageManager* mgr, void* cb);
+typedef void (*AStorageManager_obbCallbackFunc)(const char* filename, const char* state, void* data);
 
 /**
- * Attempts to mount an OBB file.
+ * Callback to call when requested asynchronous OBB operation is complete.
+ */
+void AStorageManager_setObbCallback(AStorageManager* mgr, AStorageManager_obbCallbackFunc cb, void* data);
+
+/**
+ * Attempts to mount an OBB file. This is an asynchronous operation.
  */
 void AStorageManager_mountObb(AStorageManager* mgr, const char* filename, const char* key);
 
 /**
- * Attempts to unmount an OBB file.
+ * Attempts to unmount an OBB file. This is an asynchronous operation.
  */
 void AStorageManager_unmountObb(AStorageManager* mgr, const char* filename, const int force);
 
@@ -66,4 +71,4 @@
 };
 #endif
 
-#endif      // ANDROID_PACKAGE_MANAGER_H
+#endif      // ANDROID_STORAGE_MANAGER_H