Java tutorial
//package com.java2s; import android.content.Context; import android.provider.Settings.Secure; public class Main { private static String mUniqueIdentifier = ""; public static String getUniqueIdentifier(Context context) { if (mUniqueIdentifier.isEmpty()) mUniqueIdentifier = Secure.getString(context.getContentResolver(), Secure.ANDROID_ID); return mUniqueIdentifier; } }