diff --git a/selfdrive/ui/SConscript b/selfdrive/ui/SConscript
index 52e4e0c42c..d33e576691 100644
--- a/selfdrive/ui/SConscript
+++ b/selfdrive/ui/SConscript
@@ -117,8 +117,7 @@ if arch in ['x86_64', 'Darwin'] or GetOption('extras'):
   replay_lib = qt_env.Library("qt_replay", replay_lib_src, LIBS=base_libs)
   replay_libs = [replay_lib, 'avutil', 'avcodec', 'avformat', 'bz2', 'curl', 'yuv'] + qt_libs
   qt_env.Program("replay/replay", ["replay/main.cc"], LIBS=replay_libs)
-
-  qt_env.Program("watch3", ["watch3.cc"], LIBS=qt_libs + ['common', 'json11'])
+  qt_env.Program("watch3", ["watch3.cc"], LIBS=qt_libs + ['common', 'json11', 'zmq', 'visionipc', 'messaging'])
 
   if GetOption('test'):
     qt_env.Program('replay/tests/test_replay', ['replay/tests/test_runner.cc', 'replay/tests/test_replay.cc'], LIBS=[replay_libs])
diff --git a/selfdrive/ui/qt/home.cc b/selfdrive/ui/qt/home.cc
index 1e89264952..df4f474943 100644
--- a/selfdrive/ui/qt/home.cc
+++ b/selfdrive/ui/qt/home.cc
@@ -19,7 +19,6 @@ HomeWindow::HomeWindow(QWidget* parent) : QWidget(parent) {
 
   sidebar = new Sidebar(this);
   main_layout->addWidget(sidebar);
-  QObject::connect(this, &HomeWindow::update, sidebar, &Sidebar::updateState);
   QObject::connect(sidebar, &Sidebar::openSettings, this, &HomeWindow::openSettings);
 
   slayout = new QStackedLayout();
@@ -31,15 +30,13 @@ HomeWindow::HomeWindow(QWidget* parent) : QWidget(parent) {
   onroad = new OnroadWindow(this);
   slayout->addWidget(onroad);
 
-  QObject::connect(this, &HomeWindow::update, onroad, &OnroadWindow::updateStateSignal);
-  QObject::connect(this, &HomeWindow::offroadTransitionSignal, onroad, &OnroadWindow::offroadTransitionSignal);
-
   driver_view = new DriverViewWindow(this);
   connect(driver_view, &DriverViewWindow::done, [=] {
     showDriverView(false);
   });
   slayout->addWidget(driver_view);
   setAttribute(Qt::WA_NoSystemBackground);
+  QObject::connect(uiState(), &UIState::offroadTransition, this, &HomeWindow::offroadTransition);
 }
 
 void HomeWindow::showSidebar(bool show) {
@@ -53,7 +50,6 @@ void HomeWindow::offroadTransition(bool offroad) {
   } else {
     slayout->setCurrentWidget(onroad);
   }
-  emit offroadTransitionSignal(offroad);
 }
 
 void HomeWindow::showDriverView(bool show) {
diff --git a/selfdrive/ui/qt/home.h b/selfdrive/ui/qt/home.h
index 0e65ef05e9..732071c153 100644
--- a/selfdrive/ui/qt/home.h
+++ b/selfdrive/ui/qt/home.h
@@ -43,10 +43,6 @@ signals:
   void openSettings();
   void closeSettings();
 
-  // forwarded signals
-  void update(const UIState &s);
-  void offroadTransitionSignal(bool offroad);
-
 public slots:
   void offroadTransition(bool offroad);
   void showDriverView(bool show);
diff --git a/selfdrive/ui/qt/maps/map.cc b/selfdrive/ui/qt/maps/map.cc
index e1bfe96c8e..7bf5f0b4d1 100644
--- a/selfdrive/ui/qt/maps/map.cc
+++ b/selfdrive/ui/qt/maps/map.cc
@@ -106,7 +106,7 @@ void MapWindow::initLayers() {
 }
 
 void MapWindow::timerUpdate() {
-  if (!QUIState::ui_state.scene.started) {
+  if (!uiState()->scene.started) {
     return;
   }
 
@@ -387,7 +387,7 @@ void MapInstructions::updateDistance(float d) {
   d = std::max(d, 0.0f);
   QString distance_str;
 
-  if (QUIState::ui_state.scene.is_metric) {
+  if (uiState()->scene.is_metric) {
     if (d > 500) {
       distance_str.setNum(d / 1000, 'f', 1);
       distance_str += " km";
@@ -620,7 +620,7 @@ void MapETA::updateETA(float s, float s_typical, float d) {
   // Distance
   QString distance_str;
   float num = 0;
-  if (QUIState::ui_state.scene.is_metric) {
+  if (uiState()->scene.is_metric) {
     num = d / 1000.0;
     distance_unit->setText("km");
   } else {
diff --git a/selfdrive/ui/qt/offroad/settings.cc b/selfdrive/ui/qt/offroad/settings.cc
index a0123e75fe..1819f7b5a8 100644
--- a/selfdrive/ui/qt/offroad/settings.cc
+++ b/selfdrive/ui/qt/offroad/settings.cc
@@ -98,7 +98,7 @@ TogglesPanel::TogglesPanel(SettingsWindow *parent) : ListWidget(parent) {
     bool locked = params.getBool((param + "Lock").toStdString());
     toggle->setEnabled(!locked);
     if (!locked) {
-      connect(parent, &SettingsWindow::offroadTransition, toggle, &ParamControl::setEnabled);
+      connect(uiState(), &UIState::offroadTransition, toggle, &ParamControl::setEnabled);
     }
     addItem(toggle);
   }
@@ -144,7 +144,7 @@ DevicePanel::DevicePanel(SettingsWindow *parent) : ListWidget(parent) {
     addItem(regulatoryBtn);
   }
 
-  QObject::connect(parent, &SettingsWindow::offroadTransition, [=](bool offroad) {
+  QObject::connect(uiState(), &UIState::offroadTransition, [=](bool offroad) {
     for (auto btn : findChildren<ButtonControl *>()) {
       btn->setEnabled(offroad);
     }
@@ -198,10 +198,10 @@ void DevicePanel::updateCalibDescription() {
 }
 
 void DevicePanel::reboot() {
-  if (QUIState::ui_state.status == UIStatus::STATUS_DISENGAGED) {
+  if (uiState()->status == UIStatus::STATUS_DISENGAGED) {
     if (ConfirmationDialog::confirm("Are you sure you want to reboot?", this)) {
       // Check engaged again in case it changed while the dialog was open
-      if (QUIState::ui_state.status == UIStatus::STATUS_DISENGAGED) {
+      if (uiState()->status == UIStatus::STATUS_DISENGAGED) {
         Params().putBool("DoReboot", true);
       }
     }
@@ -211,10 +211,10 @@ void DevicePanel::reboot() {
 }
 
 void DevicePanel::poweroff() {
-  if (QUIState::ui_state.status == UIStatus::STATUS_DISENGAGED) {
+  if (uiState()->status == UIStatus::STATUS_DISENGAGED) {
     if (ConfirmationDialog::confirm("Are you sure you want to power off?", this)) {
       // Check engaged again in case it changed while the dialog was open
-      if (QUIState::ui_state.status == UIStatus::STATUS_DISENGAGED) {
+      if (uiState()->status == UIStatus::STATUS_DISENGAGED) {
         Params().putBool("DoShutdown", true);
       }
     }
@@ -247,7 +247,7 @@ SoftwarePanel::SoftwarePanel(QWidget* parent) : ListWidget(parent) {
       params.putBool("DoUninstall", true);
     }
   });
-  connect(parent, SIGNAL(offroadTransition(bool)), uninstallBtn, SLOT(setEnabled(bool)));
+  connect(uiState(), &UIState::offroadTransition, uninstallBtn, &QPushButton::setEnabled);
 
   QWidget *widgets[] = {versionLbl, lastUpdateLbl, updateBtn, gitBranchLbl, gitCommitLbl, osVersionLbl, uninstallBtn};
   for (QWidget* w : widgets) {
diff --git a/selfdrive/ui/qt/offroad/settings.h b/selfdrive/ui/qt/offroad/settings.h
index f69c080ee7..c3acf3d94a 100644
--- a/selfdrive/ui/qt/offroad/settings.h
+++ b/selfdrive/ui/qt/offroad/settings.h
@@ -24,7 +24,6 @@ protected:
 
 signals:
   void closeSettings();
-  void offroadTransition(bool offroad);
   void reviewTrainingGuide();
   void showDriverView();
 
diff --git a/selfdrive/ui/qt/onroad.cc b/selfdrive/ui/qt/onroad.cc
index 53cc963674..e9f9bbfa09 100644
--- a/selfdrive/ui/qt/onroad.cc
+++ b/selfdrive/ui/qt/onroad.cc
@@ -41,8 +41,8 @@ OnroadWindow::OnroadWindow(QWidget *parent) : QWidget(parent) {
   alerts->raise();
 
   setAttribute(Qt::WA_OpaquePaintEvent);
-  QObject::connect(this, &OnroadWindow::updateStateSignal, this, &OnroadWindow::updateState);
-  QObject::connect(this, &OnroadWindow::offroadTransitionSignal, this, &OnroadWindow::offroadTransition);
+  QObject::connect(uiState(), &UIState::uiUpdate, this, &OnroadWindow::updateState);
+  QObject::connect(uiState(), &UIState::offroadTransition, this, &OnroadWindow::offroadTransition);
 }
 
 void OnroadWindow::updateState(const UIState &s) {
@@ -76,10 +76,10 @@ void OnroadWindow::mousePressEvent(QMouseEvent* e) {
 void OnroadWindow::offroadTransition(bool offroad) {
 #ifdef ENABLE_MAPS
   if (!offroad) {
-    if (map == nullptr && (QUIState::ui_state.has_prime || !MAPBOX_TOKEN.isEmpty())) {
+    if (map == nullptr && (uiState()->has_prime || !MAPBOX_TOKEN.isEmpty())) {
       MapWindow * m = new MapWindow(get_mapbox_settings());
       m->setFixedWidth(topWidget(this)->width() / 2);
-      QObject::connect(this, &OnroadWindow::offroadTransitionSignal, m, &MapWindow::offroadTransition);
+      QObject::connect(uiState(), &UIState::offroadTransition, m, &MapWindow::offroadTransition);
       split->addWidget(m, 0, Qt::AlignRight);
       map = m;
     }
@@ -274,7 +274,7 @@ void NvgWindow::initializeGL() {
 void NvgWindow::updateFrameMat(int w, int h) {
   CameraViewWidget::updateFrameMat(w, h);
 
-  UIState *s = &QUIState::ui_state;
+  UIState *s = uiState();
   s->fb_w = w;
   s->fb_h = h;
   auto intrinsic_matrix = s->wide_camera ? ecam_intrinsic_matrix : fcam_intrinsic_matrix;
@@ -348,7 +348,7 @@ void NvgWindow::drawLead(QPainter &painter, const cereal::ModelDataV2::LeadDataV
 void NvgWindow::paintGL() {
   CameraViewWidget::paintGL();
 
-  UIState *s = &QUIState::ui_state;
+  UIState *s = uiState();
   if (s->scene.world_objects_visible) {
     QPainter painter(this);
     painter.setRenderHint(QPainter::Antialiasing);
@@ -379,6 +379,6 @@ void NvgWindow::paintGL() {
 void NvgWindow::showEvent(QShowEvent *event) {
   CameraViewWidget::showEvent(event);
 
-  ui_update_params(&QUIState::ui_state);
+  ui_update_params(uiState());
   prev_draw_t = millis_since_boot();
 }
diff --git a/selfdrive/ui/qt/onroad.h b/selfdrive/ui/qt/onroad.h
index 37460c8ba6..05811c5060 100644
--- a/selfdrive/ui/qt/onroad.h
+++ b/selfdrive/ui/qt/onroad.h
@@ -97,10 +97,6 @@ private:
   QWidget *map = nullptr;
   QHBoxLayout* split;
 
-signals:
-  void updateStateSignal(const UIState &s);
-  void offroadTransitionSignal(bool offroad);
-
 private slots:
   void offroadTransition(bool offroad);
   void updateState(const UIState &s);
diff --git a/selfdrive/ui/qt/request_repeater.cc b/selfdrive/ui/qt/request_repeater.cc
index d2c0f9bc30..7ef1c833ab 100644
--- a/selfdrive/ui/qt/request_repeater.cc
+++ b/selfdrive/ui/qt/request_repeater.cc
@@ -5,7 +5,7 @@ RequestRepeater::RequestRepeater(QObject *parent, const QString &requestURL, con
   timer = new QTimer(this);
   timer->setTimerType(Qt::VeryCoarseTimer);
   QObject::connect(timer, &QTimer::timeout, [=]() {
-    if ((!QUIState::ui_state.scene.started || while_onroad) && QUIState::ui_state.awake && !active()) {
+    if ((!uiState()->scene.started || while_onroad) && uiState()->awake && !active()) {
       sendRequest(requestURL);
     }
   });
diff --git a/selfdrive/ui/qt/sidebar.cc b/selfdrive/ui/qt/sidebar.cc
index 73c4e2f8ce..e8804bc059 100644
--- a/selfdrive/ui/qt/sidebar.cc
+++ b/selfdrive/ui/qt/sidebar.cc
@@ -34,6 +34,8 @@ Sidebar::Sidebar(QWidget *parent) : QFrame(parent) {
   setAttribute(Qt::WA_OpaquePaintEvent);
   setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Expanding);
   setFixedWidth(300);
+
+  QObject::connect(uiState(), &UIState::uiUpdate, this, &Sidebar::updateState);
 }
 
 void Sidebar::mouseReleaseEvent(QMouseEvent *event) {
diff --git a/selfdrive/ui/qt/widgets/prime.cc b/selfdrive/ui/qt/widgets/prime.cc
index ab6dc67d36..2e9a9e6af9 100644
--- a/selfdrive/ui/qt/widgets/prime.cc
+++ b/selfdrive/ui/qt/widgets/prime.cc
@@ -314,8 +314,8 @@ void SetupWidget::replyFinished(const QString &response, bool success) {
 
     bool prime = json["prime"].toBool();
 
-    if (QUIState::ui_state.has_prime != prime) {
-      QUIState::ui_state.has_prime = prime;
+    if (uiState()->has_prime != prime) {
+      uiState()->has_prime = prime;
       Params().putBool("HasPrime", prime);
     }
 
diff --git a/selfdrive/ui/qt/window.cc b/selfdrive/ui/qt/window.cc
index da83bb97e4..0fee52f736 100644
--- a/selfdrive/ui/qt/window.cc
+++ b/selfdrive/ui/qt/window.cc
@@ -12,14 +12,10 @@ MainWindow::MainWindow(QWidget *parent) : QWidget(parent) {
   main_layout->addWidget(homeWindow);
   QObject::connect(homeWindow, &HomeWindow::openSettings, this, &MainWindow::openSettings);
   QObject::connect(homeWindow, &HomeWindow::closeSettings, this, &MainWindow::closeSettings);
-  QObject::connect(&qs, &QUIState::uiUpdate, homeWindow, &HomeWindow::update);
-  QObject::connect(&qs, &QUIState::offroadTransition, homeWindow, &HomeWindow::offroadTransition);
-  QObject::connect(&qs, &QUIState::offroadTransition, homeWindow, &HomeWindow::offroadTransitionSignal);
 
   settingsWindow = new SettingsWindow(this);
   main_layout->addWidget(settingsWindow);
   QObject::connect(settingsWindow, &SettingsWindow::closeSettings, this, &MainWindow::closeSettings);
-  QObject::connect(&qs, &QUIState::offroadTransition, settingsWindow, &SettingsWindow::offroadTransition);
   QObject::connect(settingsWindow, &SettingsWindow::reviewTrainingGuide, [=]() {
     onboardingWindow->showTrainingGuide();
     main_layout->setCurrentWidget(onboardingWindow);
@@ -37,8 +33,7 @@ MainWindow::MainWindow(QWidget *parent) : QWidget(parent) {
     main_layout->setCurrentWidget(onboardingWindow);
   }
 
-  QObject::connect(&qs, &QUIState::uiUpdate, &device, &Device::update);
-  QObject::connect(&qs, &QUIState::offroadTransition, [=](bool offroad) {
+  QObject::connect(uiState(), &UIState::offroadTransition, [=](bool offroad) {
     if (!offroad) {
       closeSettings();
     }
@@ -79,7 +74,7 @@ void MainWindow::openSettings() {
 void MainWindow::closeSettings() {
   main_layout->setCurrentWidget(homeWindow);
 
-  if (QUIState::ui_state.scene.started) {
+  if (uiState()->scene.started) {
     homeWindow->showSidebar(false);
   }
 }
diff --git a/selfdrive/ui/qt/window.h b/selfdrive/ui/qt/window.h
index 069831cffe..0bd328aa8a 100644
--- a/selfdrive/ui/qt/window.h
+++ b/selfdrive/ui/qt/window.h
@@ -19,7 +19,6 @@ private:
   void closeSettings();
 
   Device device;
-  QUIState qs;
 
   QStackedLayout *main_layout;
   HomeWindow *homeWindow;
diff --git a/selfdrive/ui/ui.cc b/selfdrive/ui/ui.cc
index 3dd044653b..a8453889cb 100644
--- a/selfdrive/ui/ui.cc
+++ b/selfdrive/ui/ui.cc
@@ -218,41 +218,43 @@ static void update_status(UIState *s) {
 }
 
 
-QUIState::QUIState(QObject *parent) : QObject(parent) {
-  ui_state.sm = std::make_unique<SubMaster, const std::initializer_list<const char *>>({
+UIState::UIState(QObject *parent) : QObject(parent) {
+  sm = std::make_unique<SubMaster, const std::initializer_list<const char *>>({
     "modelV2", "controlsState", "liveCalibration", "radarState", "deviceState", "roadCameraState",
     "pandaStates", "carParams", "driverMonitoringState", "sensorEvents", "carState", "liveLocationKalman",
   });
 
   Params params;
-  ui_state.wide_camera = Hardware::TICI() ? params.getBool("EnableWideCamera") : false;
-  ui_state.has_prime = params.getBool("HasPrime");
+  wide_camera = Hardware::TICI() ? params.getBool("EnableWideCamera") : false;
+  has_prime = params.getBool("HasPrime");
 
   // update timer
   timer = new QTimer(this);
-  QObject::connect(timer, &QTimer::timeout, this, &QUIState::update);
+  QObject::connect(timer, &QTimer::timeout, this, &UIState::update);
   timer->start(1000 / UI_FREQ);
 }
 
-void QUIState::update() {
-  update_sockets(&ui_state);
-  update_state(&ui_state);
-  update_status(&ui_state);
+void UIState::update() {
+  update_sockets(this);
+  update_state(this);
+  update_status(this);
 
-  if (ui_state.scene.started != started_prev || ui_state.sm->frame == 1) {
-    started_prev = ui_state.scene.started;
-    emit offroadTransition(!ui_state.scene.started);
+  if (scene.started != started_prev || sm->frame == 1) {
+    started_prev = scene.started;
+    emit offroadTransition(!scene.started);
   }
 
-  if (ui_state.sm->frame % UI_FREQ == 0) {
+  if (sm->frame % UI_FREQ == 0) {
     watchdog_kick();
   }
-  emit uiUpdate(ui_state);
+  emit uiUpdate(*this);
 }
 
 Device::Device(QObject *parent) : brightness_filter(BACKLIGHT_OFFROAD, BACKLIGHT_TS, BACKLIGHT_DT), QObject(parent) {
   setAwake(true);
   resetInteractiveTimout();
+
+  QObject::connect(uiState(), &UIState::uiUpdate, this, &Device::update);
 }
 
 void Device::update(const UIState &s) {
@@ -260,7 +262,7 @@ void Device::update(const UIState &s) {
   updateWakefulness(s);
 
   // TODO: remove from UIState and use signals
-  QUIState::ui_state.awake = awake;
+  uiState()->awake = awake;
 }
 
 void Device::setAwake(bool on) {
@@ -329,3 +331,8 @@ void Device::updateWakefulness(const UIState &s) {
 
   setAwake(s.scene.ignition || interactive_timeout > 0);
 }
+
+UIState *uiState() {
+  static UIState ui_state;
+  return &ui_state;
+}
diff --git a/selfdrive/ui/ui.h b/selfdrive/ui/ui.h
index 924fb8194c..7c16e4ae6f 100644
--- a/selfdrive/ui/ui.h
+++ b/selfdrive/ui/ui.h
@@ -101,7 +101,12 @@ typedef struct UIScene {
   uint64_t started_frame;
 } UIScene;
 
-typedef struct UIState {
+class UIState : public QObject {
+  Q_OBJECT
+
+public:
+  UIState(QObject* parent = 0);
+
   int fb_w = 0, fb_h = 0;
 
   std::unique_ptr<SubMaster> sm;
@@ -114,17 +119,6 @@ typedef struct UIState {
 
   QTransform car_space_transform;
   bool wide_camera;
-} UIState;
-
-
-class QUIState : public QObject {
-  Q_OBJECT
-
-public:
-  QUIState(QObject* parent = 0);
-
-  // TODO: get rid of this, only use signal
-  inline static UIState ui_state = {0};
 
 signals:
   void uiUpdate(const UIState &s);
@@ -138,6 +132,7 @@ private:
   bool started_prev = true;
 };
 
+UIState *uiState();
 
 // device management class