diff --git a/qomemo/CMakeLists.txt b/qomemo/CMakeLists.txt
index e8e4502..40abc25 100644
--- a/qomemo/CMakeLists.txt
+++ b/qomemo/CMakeLists.txt
@@ -1,8 +1,14 @@
 target_sources(squawk PRIVATE
+  device_key_storage.cpp
+  device_key_storage.h
+  device_service.cpp
+  device_service.h
   signal.h
   signal.cpp
   qomemo.cpp
   qomemo.h
   sce.cpp
   sce.h
+  user_device_list.cpp
+  user_device_list.h
   )
\ No newline at end of file
diff --git a/qomemo/device_key_storage.cpp b/qomemo/device_key_storage.cpp
new file mode 100644
index 0000000..1ba017e
--- /dev/null
+++ b/qomemo/device_key_storage.cpp
@@ -0,0 +1,15 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#include "device_key_storage.h"
+#include <QRandomGenerator>
+
+int QXmpp::Omemo::DeviceKeyStorage::generateDeviceId() {
+  QRandomGenerator random{};
+
+  return 1 + random.bounded(INT32_MAX - 1);
+}
+
+QXmpp::Omemo::DeviceKeyStorage::DeviceKeyStorage(int deviceId)
+    : deviceId(deviceId) {}
diff --git a/qomemo/device_key_storage.h b/qomemo/device_key_storage.h
new file mode 100644
index 0000000..a0d8ce2
--- /dev/null
+++ b/qomemo/device_key_storage.h
@@ -0,0 +1,18 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#pragma once
+
+namespace QXmpp::Omemo {
+
+class DeviceKeyStorage {
+public:
+  static int generateDeviceId();
+
+  explicit DeviceKeyStorage(int deviceId);
+
+  const int deviceId;
+};
+
+} // namespace QXmpp::Omemo
diff --git a/qomemo/device_service.cpp b/qomemo/device_service.cpp
new file mode 100644
index 0000000..4333d7f
--- /dev/null
+++ b/qomemo/device_service.cpp
@@ -0,0 +1,30 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#include "device_service.h"
+
+#include <QXmppClient.h>
+#include <QXmppPubSubIq.h>
+
+#include <QDebug>
+
+QXmpp::Omemo::DeviceService::DeviceService(QXmppClient &client, QObject *parent)
+    : QObject(parent), client(client) {
+  connect(&client, &QXmppClient::iqReceived, this,
+          &DeviceService::onIqReceived);
+}
+
+void QXmpp::Omemo::DeviceService::onIqReceived(const QXmppIq &iq) {
+  // Update OMEMO device list
+}
+
+void QXmpp::Omemo::DeviceService::fetch() {
+  QXmppPubSubIq fetchOwnDevices{};
+  fetchOwnDevices.setFrom(client.configuration().jid());
+  fetchOwnDevices.setTo(client.configuration().jidBare());
+  fetchOwnDevices.setType(QXmppIq::Get);
+  fetchOwnDevices.setQueryNode("urn:xmpp:omemo:1:devices");
+
+  client.sendPacket(fetchOwnDevices);
+}
diff --git a/qomemo/device_service.h b/qomemo/device_service.h
new file mode 100644
index 0000000..fc2e4d5
--- /dev/null
+++ b/qomemo/device_service.h
@@ -0,0 +1,31 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#pragma once
+
+#include "user_device_list.h"
+
+#include <QXmppClient.h>
+
+namespace QXmpp::Omemo {
+
+class DeviceService : public QObject {
+  Q_OBJECT
+
+public:
+  DeviceService(QXmppClient& client, QObject *parent);
+
+  void fetch();
+
+public slots:
+  void onIqReceived(const QXmppIq& iq);
+
+private:
+  void announce();
+
+  QXmppClient& client;
+  QMap<QString, UserDeviceList> device_lists{};
+};
+
+} // namespace QXmpp::Omemo
diff --git a/qomemo/qomemo.h b/qomemo/qomemo.h
index 906d0ba..e815d11 100644
--- a/qomemo/qomemo.h
+++ b/qomemo/qomemo.h
@@ -91,4 +91,4 @@ public:
   QXmppMessage message{};
 };
 
-} // namespace QOmemo
+} // namespace QXmpp::Omemo
diff --git a/qomemo/user_device_list.cpp b/qomemo/user_device_list.cpp
new file mode 100644
index 0000000..9a3f18a
--- /dev/null
+++ b/qomemo/user_device_list.cpp
@@ -0,0 +1,10 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#include "user_device_list.h"
+
+#include <utility>
+
+QXmpp::Omemo::UserDeviceList::UserDeviceList(QString jid)
+    : jid(std::move(jid)) {}
diff --git a/qomemo/user_device_list.h b/qomemo/user_device_list.h
new file mode 100644
index 0000000..26a88ca
--- /dev/null
+++ b/qomemo/user_device_list.h
@@ -0,0 +1,17 @@
+/*
+ * Created by victoria on 2021-05-12.
+ */
+
+#pragma once
+
+#include <QString>
+namespace QXmpp::Omemo {
+
+class UserDeviceList {
+public:
+  explicit UserDeviceList(QString jid);
+
+  const QString jid;
+};
+
+} // namespace QXmpp::Omemo