DownloadManager manager = DownloadManager.getInstance(this);
manager.setApkName("QQ.apk")
.setApkUrl("http://gdown.baidu.com/data/wisegame/74dadae1bde205b0/QQ_776.apk")
.setDownloadPath(Environment.getExternalStorageDirectory() + "/AppUpdate")
.setSmallIcon(R.mipmap.ic_launcher)
// 可设置, 可不设置
.setConfiguration(configuration)
.download();
来源: http://blog.csdn.net/a_zhon/article/details/79215433