Unique ID for each user in Android
<p>I want to allocate unique ID to each user as soon as he installs the application so that whenever the app contacts the server I know who is contacting.
For this purpose, I thought that on first time installation, the app contacts the server and gets unique ID. But I don't know where to store it permanently so that next time when app is started, it knows what its ID is rather than contacting server.</p>

<p>Sorry if that is some obvious question as I am newbie.</p>
