diff --git a/core/java/android/bluetooth/BluetoothDevice.java b/core/java/android/bluetooth/BluetoothDevice.java
index e0b03d22abe93..f158f5f29ecdf 100644
--- a/core/java/android/bluetooth/BluetoothDevice.java
+++ b/core/java/android/bluetooth/BluetoothDevice.java
@@ -1714,7 +1714,7 @@ public final class BluetoothDevice implements Parcelable {
      *             an d{@link BluetoothDevice#PHY_LE_CODED_MASK}. This option does not take effect
      *             if {@code autoConnect} is set to true.
      * @param handler The handler to use for the callback. If {@code null}, callbacks will happen
-     *             on the service's main thread.
+     *             on an un-specified background thread.
      * @throws NullPointerException if callback is null
      */
     public BluetoothGatt connectGatt(Context context, boolean autoConnect,
@@ -1723,9 +1723,6 @@ public final class BluetoothDevice implements Parcelable {
         if (callback == null)
             throw new NullPointerException("callback is null");
 
-        if (handler == null)
-            handler = new Handler(Looper.getMainLooper());
-
         // TODO(Bluetooth) check whether platform support BLE
         //     Do the check here or in GattServer?
         BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
diff --git a/core/java/android/bluetooth/BluetoothGatt.java b/core/java/android/bluetooth/BluetoothGatt.java
index 40f10a8edd227..3135b30ebcc83 100644
--- a/core/java/android/bluetooth/BluetoothGatt.java
+++ b/core/java/android/bluetooth/BluetoothGatt.java
@@ -156,7 +156,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                 }
                 mClientIf = clientIf;
                 if (status != GATT_SUCCESS) {
-                    mHandler.post(new Runnable() {
+                    runOrQueueCallback(new Runnable() {
                         @Override
                         public void run() {
                             if (mCallback != null) {
@@ -191,7 +191,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     return;
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -213,7 +213,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     return;
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -238,7 +238,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                 int profileState = connected ? BluetoothProfile.STATE_CONNECTED :
                                                BluetoothProfile.STATE_DISCONNECTED;
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -300,7 +300,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     }
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -352,7 +352,7 @@ public final class BluetoothGatt implements BluetoothProfile {
 
                 if (status == 0) characteristic.setValue(value);
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -401,7 +401,7 @@ public final class BluetoothGatt implements BluetoothProfile {
 
                 mAuthRetryState = AUTH_RETRY_STATE_IDLE;
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -430,7 +430,7 @@ public final class BluetoothGatt implements BluetoothProfile {
 
                 characteristic.setValue(value);
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -477,7 +477,7 @@ public final class BluetoothGatt implements BluetoothProfile {
 
                 mAuthRetryState = AUTH_RETRY_STATE_IDLE;
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -523,7 +523,7 @@ public final class BluetoothGatt implements BluetoothProfile {
 
                 mAuthRetryState = AUTH_RETRY_STATE_IDLE;
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -549,7 +549,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     mDeviceBusy = false;
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -570,7 +570,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                 if (!address.equals(mDevice.getAddress())) {
                     return;
                 }
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -592,7 +592,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     return;
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -616,7 +616,7 @@ public final class BluetoothGatt implements BluetoothProfile {
                     return;
                 }
 
-                mHandler.post(new Runnable() {
+                runOrQueueCallback(new Runnable() {
                     @Override
                     public void run() {
                         if (mCallback != null) {
@@ -702,6 +702,22 @@ public final class BluetoothGatt implements BluetoothProfile {
         return null;
     }
 
+    /**
+     * Queue the runnable on a {@link Handler} provided by the user, or execute the runnable
+     * immediately if no Handler was provided.
+     */
+    private void runOrQueueCallback(final Runnable cb) {
+        if (mHandler == null) {
+          try {
+            cb.run();
+          } catch (Exception ex) {
+            Log.w(TAG, "Unhandled exception in callback", ex);
+          }
+        } else {
+          mHandler.post(cb);
+        }
+    }
+
     /**
      * Register an application callback to start using GATT.
      *