diff --git a/Engine/system/api/iosapi.h b/Engine/system/api/iosapi.h
index c9f837dc..440917bc 100644
--- a/Engine/system/api/iosapi.h
+++ b/Engine/system/api/iosapi.h
@@ -28,6 +28,7 @@ class iOSApi final: SystemApi {
     void     implProcessEvents(AppCallBack& cb) override;
 
     void     implSetWindowTitle(SystemApi::Window *w, const char* utf8) override;
+    void     implSetAllowedOrientations(SystemApi::Window *w, Orientation orientations) override;
 
   friend class SystemApi;
   };
diff --git a/Engine/system/api/iosapi.mm b/Engine/system/api/iosapi.mm
index 0f78f751..8539dbd0 100644
--- a/Engine/system/api/iosapi.mm
+++ b/Engine/system/api/iosapi.mm
@@ -15,6 +15,19 @@
 
 using namespace Tempest;
 
+static UIInterfaceOrientationMask nativeFormat(SystemApi::Orientation orientations) {
+  UIInterfaceOrientationMask mask = 0;
+  if(orientations & SystemApi::Portrait)
+    mask |= UIInterfaceOrientationMaskPortrait;
+  if(orientations & SystemApi::PortraitUpsideDown)
+    mask |= UIInterfaceOrientationMaskPortraitUpsideDown;
+  if(orientations & SystemApi::LandscapeLeft)
+    mask |= UIInterfaceOrientationMaskLandscapeLeft;
+  if(orientations & SystemApi::LandscapeRight)
+    mask |= UIInterfaceOrientationMaskLandscapeRight;
+  return mask;
+  }
+
 #if TARGET_CPU_X86_64
 #  define FUNCTION_CALL_ALIGNMENT 16
 #  define SET_STACK_POINTER "movq %0, %%rsp"
@@ -238,16 +251,20 @@ static void discardPendingEvent(TempestWindow* window) {
 
 @interface ViewController:UIViewController{}
 -(id)init;
+-(void)setAllowedOrientations:(UIInterfaceOrientationMask)mask;
 @end
 
 @implementation ViewController {
   bool fullScreen;
+  UIInterfaceOrientationMask allowedOrientations;
   }
 
 -(id)init {
   self = [super init];
-  if(self!=nil)
+  if(self!=nil) {
     fullScreen = true;
+    allowedOrientations = UIInterfaceOrientationMaskAll;
+    }
   return self;
   }
 
@@ -274,7 +291,19 @@ - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interface
   }
 
 -(UIInterfaceOrientationMask)supportedInterfaceOrientations {
-  return UIInterfaceOrientationMaskAll;
+  return allowedOrientations;
+  }
+
+-(void)setAllowedOrientations:(UIInterfaceOrientationMask)mask {
+  if(allowedOrientations==mask)
+    return;
+  allowedOrientations = mask;
+  // Reevaluate on UIKit's stack after the engine yields.
+  dispatch_async(dispatch_get_main_queue(), ^{
+    if(@available(iOS 16.0, *))
+      [self setNeedsUpdateOfSupportedInterfaceOrientations]; else
+      [UIViewController attemptRotationToDeviceOrientation];
+    });
   }
 
 -(bool)setAsFullscreen: (bool)value {
@@ -386,11 +415,6 @@ - (UISceneConfiguration *)application:(UIApplication *)application
   return configuration;
   }
 
-- (UIInterfaceOrientationMask)application:(UIApplication *)application
-  supportedInterfaceOrientationsForWindow:(UIWindow *)window {
-  return UIInterfaceOrientationMaskAll;
-  }
-
 - (void)applicationWillTerminate:(UIApplication *)application {
   (void)application;
   }
@@ -492,6 +516,8 @@ static void appleMain(void*) {
   auto delegate = (TempestSceneDelegate*)windowScene.delegate;
   delegate.window = window;
 
+  auto controller = (ViewController*)window.rootViewController;
+  [controller setAllowedOrientations:UIInterfaceOrientationMaskAll];
   [window makeKeyAndVisible];
 
   window->owner = owner;
@@ -549,6 +575,16 @@ static void appleMain(void*) {
   return [ctrl isFullscreen];
   }
 
+void iOSApi::implSetAllowedOrientations(Window* w, Orientation orientations) {
+  const auto mask = nativeFormat(orientations);
+  if(mask==0)
+    return;
+
+  auto wx = reinterpret_cast<TempestWindow*>(w);
+  auto ctrl = (ViewController*)wx.rootViewController;
+  [ctrl setAllowedOrientations:mask];
+  }
+
 void iOSApi::implSetCursorPosition(Window* w, int x, int y) {
   }
 
diff --git a/Engine/system/systemapi.cpp b/Engine/system/systemapi.cpp
index 04e3d1dd..217b241a 100644
--- a/Engine/system/systemapi.cpp
+++ b/Engine/system/systemapi.cpp
@@ -33,6 +33,9 @@ void SystemApi::implSetWindowTitle(Window *w, const char *utf8) {
   // TODO
   }
 
+void SystemApi::implSetAllowedOrientations(Window*, Orientation) {
+  }
+
 void SystemApi::setupKeyTranslate(const TranslateKeyPair k[], uint16_t funcCount ) {
   m.keys.clear();
   m.a. clear();
@@ -200,6 +203,10 @@ void SystemApi::setWindowTitle(Window *w, const char *utf8) {
   return inst().implSetWindowTitle(w, utf8);
   }
 
+void SystemApi::setAllowedOrientations(Window *w, Orientation orientations) {
+  return inst().implSetAllowedOrientations(w, orientations);
+  }
+
 void SystemApi::setCursorPosition(SystemApi::Window *w, int x, int y) {
   return inst().implSetCursorPosition(w,x,y);
   }
diff --git a/Engine/system/systemapi.h b/Engine/system/systemapi.h
index 31482d0f..6234b226 100644
--- a/Engine/system/systemapi.h
+++ b/Engine/system/systemapi.h
@@ -34,6 +34,15 @@ class SystemApi {
       Hidden, //internal
       };
 
+    enum Orientation : uint8_t {
+      Portrait           = 1 << 0,
+      PortraitUpsideDown = 1 << 1,
+      LandscapeLeft      = 1 << 2,
+      LandscapeRight     = 1 << 3,
+      Landscape          = LandscapeLeft | LandscapeRight,
+      AllOrientations    = Portrait | PortraitUpsideDown | Landscape,
+      };
+
     struct TranslateKeyPair final {
       uint16_t src;
       uint16_t result;
@@ -51,6 +60,7 @@ class SystemApi {
     static bool     isFullscreen(SystemApi::Window *w);
 
     static void     setWindowTitle(SystemApi::Window *w, const char* utf8);
+    static void     setAllowedOrientations(SystemApi::Window *w, Orientation orientations);
     static float    uiScale(SystemApi::Window *w);
 
     static uint16_t translateKey(uint64_t scancode);
@@ -86,6 +96,7 @@ class SystemApi {
     virtual void     implProcessEvents(AppCallBack& cb) = 0;
 
     virtual void     implSetWindowTitle(SystemApi::Window *w, const char* utf8) = 0;
+    virtual void     implSetAllowedOrientations(SystemApi::Window *w, Orientation orientations);
 
     static void      setCursorPosition(SystemApi::Window *w, int x, int y);
     static void      showCursor(SystemApi::Window *w, CursorShape c);
diff --git a/Engine/ui/window.cpp b/Engine/ui/window.cpp
index de00eb2c..255fd8d7 100644
--- a/Engine/ui/window.cpp
+++ b/Engine/ui/window.cpp
@@ -31,6 +31,10 @@ void Window::setWindowTitle(const char* utf8) {
   Tempest::SystemApi::setWindowTitle(hwnd(), utf8);
   }
 
+void Window::setAllowedOrientations(Orientation orientations) {
+  Tempest::SystemApi::setAllowedOrientations(hwnd(), SystemApi::Orientation(orientations));
+  }
+
 void Window::render() {
   }
 
diff --git a/Engine/ui/window.h b/Engine/ui/window.h
index 9217073e..2b030565 100644
--- a/Engine/ui/window.h
+++ b/Engine/ui/window.h
@@ -17,12 +17,25 @@ class Window : public Widget {
       FullScreen,
       };
 
+    enum Orientation : uint8_t {
+      Portrait           = 1 << 0,
+      PortraitUpsideDown = 1 << 1,
+      LandscapeLeft      = 1 << 2,
+      LandscapeRight     = 1 << 3,
+      Landscape          = LandscapeLeft | LandscapeRight,
+      AllOrientations    = Portrait | PortraitUpsideDown | Landscape,
+      };
+
     Window();
     Window( ShowMode sm );
     ~Window() override;
 
     void setWindowTitle(const char* utf8);
 
+    // App and platform restrictions still apply. AllOrientations restores the
+    // app defaults. Has no effect on platforms without orientation support.
+    void setAllowedOrientations(Orientation orientations);
+
   protected:
     virtual void render();
     using        Widget::dispatchPaintEvent;
@@ -46,4 +59,12 @@ class Window : public Widget {
   friend class SystemApi;
   };
 
+inline Window::Orientation operator | (Window::Orientation a, const Window::Orientation& b) {
+  return Window::Orientation(uint8_t(a)|uint8_t(b));
+  }
+
+inline Window::Orientation operator & (Window::Orientation a, const Window::Orientation& b) {
+  return Window::Orientation(uint8_t(a)&uint8_t(b));
+  }
+
 }