这里有30多个答案，有些是相同的，有些是独特的。这个答案是基于这些答案中的一些。其中一个是Lenn Dolling的回答。

它组合3个ID并创建32位十六进制字符串。这对我来说效果很好。

3个ID为：伪ID-根据物理设备规范生成ANDROID_ID-设置.Securite.ANDROID-ID蓝牙地址-蓝牙适配器地址

它将返回如下内容：551F27C060712A72730B0F734064B1

注意：您始终可以向longId字符串添加更多ID。例如，序列号。wifi适配器地址。伊梅。通过这种方式，您可以使每个设备都更独特。

@SuppressWarnings("deprecation")
@SuppressLint("HardwareIds")
public static String generateDeviceIdentifier(Context context) {

        String pseudoId = "35" +
                Build.BOARD.length() % 10 +
                Build.BRAND.length() % 10 +
                Build.CPU_ABI.length() % 10 +
                Build.DEVICE.length() % 10 +
                Build.DISPLAY.length() % 10 +
                Build.HOST.length() % 10 +
                Build.ID.length() % 10 +
                Build.MANUFACTURER.length() % 10 +
                Build.MODEL.length() % 10 +
                Build.PRODUCT.length() % 10 +
                Build.TAGS.length() % 10 +
                Build.TYPE.length() % 10 +
                Build.USER.length() % 10;

        String androidId = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID);

        BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        String btId = "";

        if (bluetoothAdapter != null) {
            btId = bluetoothAdapter.getAddress();
        }

        String longId = pseudoId + androidId + btId;

        try {
            MessageDigest messageDigest = MessageDigest.getInstance("MD5");
            messageDigest.update(longId.getBytes(), 0, longId.length());

            // get md5 bytes
            byte md5Bytes[] = messageDigest.digest();

            // creating a hex string
            String identifier = "";

            for (byte md5Byte : md5Bytes) {
                int b = (0xFF & md5Byte);

                // if it is a single digit, make sure it have 0 in front (proper padding)
                if (b <= 0xF) {
                    identifier += "0";
                }

                // add number to string
                identifier += Integer.toHexString(b);
            }

            // hex string to uppercase
            identifier = identifier.toUpperCase();
            return identifier;
        } catch (Exception e) {
            Log.e("TAG", e.toString());
        }
        return "";
}

Settings.Secure#ANDROID_ID返回每个用户64位十六进制字符串的唯一ANDROID ID。

import android.provider.Settings.Secure;

private String android_id = Secure.getString(getContext().getContentResolver(),
                                                        Secure.ANDROID_ID);

另请阅读唯一标识符的最佳实践：https://developer.android.com/training/articles/user-data-ids

我的两美分-注意，这是一个设备（错误）唯一ID，而不是Android开发者博客中讨论的安装ID。

值得注意的是，@emmby提供的解决方案在每个应用程序ID中都有所不同，因为SharedPreferences没有跨进程同步（请参阅此处和此处）。所以我完全避免了这一点。

相反，我封装了在枚举中获取（设备）ID的各种策略-更改枚举常量的顺序会影响获取ID的各种方式的优先级。返回第一个非空ID或抛出异常（根据不赋予空含义的良好Java实践）。例如，我先有一个TELEPHONY，但一个好的默认选择是ANDROID_ID贝塔：

import android.Manifest.permission;
import android.bluetooth.BluetoothAdapter;
import android.content.Context;
import android.content.pm.PackageManager;
import android.net.wifi.WifiManager;
import android.provider.Settings.Secure;
import android.telephony.TelephonyManager;
import android.util.Log;

// TODO : hash
public final class DeviceIdentifier {

    private DeviceIdentifier() {}

    /** @see http://code.google.com/p/android/issues/detail?id=10603 */
    private static final String ANDROID_ID_BUG_MSG = "The device suffers from "
        + "the Android ID bug - its ID is the emulator ID : "
        + IDs.BUGGY_ANDROID_ID;
    private static volatile String uuid; // volatile needed - see EJ item 71
    // need lazy initialization to get a context

    /**
     * Returns a unique identifier for this device. The first (in the order the
     * enums constants as defined in the IDs enum) non null identifier is
     * returned or a DeviceIDException is thrown. A DeviceIDException is also
     * thrown if ignoreBuggyAndroidID is false and the device has the Android ID
     * bug
     *
     * @param ctx
     *            an Android constant (to retrieve system services)
     * @param ignoreBuggyAndroidID
     *            if false, on a device with the android ID bug, the buggy
     *            android ID is not returned instead a DeviceIDException is
     *            thrown
     * @return a *device* ID - null is never returned, instead a
     *         DeviceIDException is thrown
     * @throws DeviceIDException
     *             if none of the enum methods manages to return a device ID
     */
    public static String getDeviceIdentifier(Context ctx,
            boolean ignoreBuggyAndroidID) throws DeviceIDException {
        String result = uuid;
        if (result == null) {
            synchronized (DeviceIdentifier.class) {
                result = uuid;
                if (result == null) {
                    for (IDs id : IDs.values()) {
                        try {
                            result = uuid = id.getId(ctx);
                        } catch (DeviceIDNotUniqueException e) {
                            if (!ignoreBuggyAndroidID)
                                throw new DeviceIDException(e);
                        }
                        if (result != null) return result;
                    }
                    throw new DeviceIDException();
                }
            }
        }
        return result;
    }

    private static enum IDs {
        TELEPHONY_ID {

            @Override
            String getId(Context ctx) {
                // TODO : add a SIM based mechanism ? tm.getSimSerialNumber();
                final TelephonyManager tm = (TelephonyManager) ctx
                        .getSystemService(Context.TELEPHONY_SERVICE);
                if (tm == null) {
                    w("Telephony Manager not available");
                    return null;
                }
                assertPermission(ctx, permission.READ_PHONE_STATE);
                return tm.getDeviceId();
            }
        },
        ANDROID_ID {

            @Override
            String getId(Context ctx) throws DeviceIDException {
                // no permission needed !
                final String andoidId = Secure.getString(
                    ctx.getContentResolver(),
                    android.provider.Settings.Secure.ANDROID_ID);
                if (BUGGY_ANDROID_ID.equals(andoidId)) {
                    e(ANDROID_ID_BUG_MSG);
                    throw new DeviceIDNotUniqueException();
                }
                return andoidId;
            }
        },
        WIFI_MAC {

            @Override
            String getId(Context ctx) {
                WifiManager wm = (WifiManager) ctx
                        .getSystemService(Context.WIFI_SERVICE);
                if (wm == null) {
                    w("Wifi Manager not available");
                    return null;
                }
                assertPermission(ctx, permission.ACCESS_WIFI_STATE); // I guess
                // getMacAddress() has no java doc !!!
                return wm.getConnectionInfo().getMacAddress();
            }
        },
        BLUETOOTH_MAC {

            @Override
            String getId(Context ctx) {
                BluetoothAdapter ba = BluetoothAdapter.getDefaultAdapter();
                if (ba == null) {
                    w("Bluetooth Adapter not available");
                    return null;
                }
                assertPermission(ctx, permission.BLUETOOTH);
                return ba.getAddress();
            }
        }
        // TODO PSEUDO_ID
        // http://www.pocketmagic.net/2011/02/android-unique-device-id/
        ;

        static final String BUGGY_ANDROID_ID = "9774d56d682e549c";
        private final static String TAG = IDs.class.getSimpleName();

        abstract String getId(Context ctx) throws DeviceIDException;

        private static void w(String msg) {
            Log.w(TAG, msg);
        }

        private static void e(String msg) {
            Log.e(TAG, msg);
        }
    }

    private static void assertPermission(Context ctx, String perm) {
        final int checkPermission = ctx.getPackageManager().checkPermission(
            perm, ctx.getPackageName());
        if (checkPermission != PackageManager.PERMISSION_GRANTED) {
            throw new SecurityException("Permission " + perm + " is required");
        }
    }

    // =========================================================================
    // Exceptions
    // =========================================================================
    public static class DeviceIDException extends Exception {

        private static final long serialVersionUID = -8083699995384519417L;
        private static final String NO_ANDROID_ID = "Could not retrieve a "
            + "device ID";

        public DeviceIDException(Throwable throwable) {
            super(NO_ANDROID_ID, throwable);
        }

        public DeviceIDException(String detailMessage) {
            super(detailMessage);
        }

        public DeviceIDException() {
            super(NO_ANDROID_ID);
        }
    }

    public static final class DeviceIDNotUniqueException extends
            DeviceIDException {

        private static final long serialVersionUID = -8940090896069484955L;

        public DeviceIDNotUniqueException() {
            super(ANDROID_ID_BUG_MSG);
        }
    }
}

以下代码使用隐藏的Android API返回设备序列号。但是，这个代码在三星Galaxy Tab上不起作用，因为这个设备上没有设置“ro.seriano”。

String serial = null;

try {
    Class<?> c = Class.forName("android.os.SystemProperties");
    Method get = c.getMethod("get", String.class);
    serial = (String) get.invoke(c, "ro.serialno");
}
catch (Exception ignored) {

}

当设备没有电话功能时，我使用以下代码获取IMEI或使用Secure.ANDROID_ID作为替代：

String identifier = null;
TelephonyManager tm = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE));
if (tm != null)
      identifier = tm.getDeviceId();
if (identifier == null || identifier .length() == 0)
      identifier = Secure.getString(activity.getContentResolver(),Secure.ANDROID_ID);

有很多不同的方法可以解决ANDROID_ID问题（有时可能为空，或者特定型号的设备总是返回相同的ID），有利弊：

实现自定义ID生成算法（基于应该是静态且不会更改的设备财产->谁知道呢）滥用其他ID，如IMEI、序列号、Wi-Fi/蓝牙MAC地址（它们不会存在于所有设备上，或者需要额外的权限）

我自己更喜欢使用现有的OpenUDID实现（请参见https://github.com/ylechelle/OpenUDID)适用于Android（请参见https://github.com/vieux/OpenUDID). 它很容易集成并利用ANDROID_ID和上述问题的回退。