samples/browseable/AutoBackupForApps/res/xml/backup.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2014 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.
-->
<full-backup-content xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- This file is referenced from android:fullBackupContent in AndroidManifest.xml, and controls
         exclusions/inclusions for the default backup policy. -->

    <!-- Shared preferences files can be excluded using the "sharedpref" domain. -->
    <!-- Be sure to exclude any device-specific identifiers, such as the GCM registration key. -->
    <!-- You may also wish to exclude directories that contain device-specific session tokens or
         sensitive user credentials. -->
    <exclude domain="sharedpref" path="gcm"/>
    <exclude domain="sharedpref" path="user_credentials"/>

    <!-- Databases can be excluded using the "database" domain. -->
    <exclude domain="database" path="local_secrets.db"/>

    <!-- Additional domains include "file", "external", "root", and "path". See
         http://developer.android.com/preview/backup/index.html for more details.

         Additionally, content in the cache directory, external storage, and the no_backup directory
         (see android.content.Context#getNoBackupFilesDir()) are excluded by default. If you need
         to backup data in one of these locations, use the <include> directive. -->

</full-backup-content>