diff --git a/src/app.cpp b/src/app.cpp
index e1ee65a..d8c8995 100644
--- a/src/app.cpp
+++ b/src/app.cpp
@@ -17,7 +17,7 @@ void android_async_unlock(struct engine* engine);
 #elif _WIN32
 bool async_lock_try();
 void async_lock();
-void async_swap();
+void win32_async_swap();
 void async_unlock();
 void destroy_window();
 #endif
@@ -521,6 +521,19 @@ void App::async_end()
 #endif
 }
 
+void App::async_swap()
+{
+#if __OSX__
+    [osx_view async_swap];
+#elif __IOS__
+    [ios_view async_swap];
+#elif __ANDROID__
+    android_async_swap(and_engine);
+#elif _WIN32
+    win32_async_swap();
+#endif
+}
+
 bool App::update_ui_observer(Node *n)
 {
     if (n && n->m_display)
@@ -1039,7 +1052,7 @@ void App::render_thread_main()
         // execute the tasks
         if (!working_list.empty())
         {
-            async_lock();
+            async_start();
             while (!working_list.empty())
             {
                 //LOG("render task %d", count);
@@ -1047,7 +1060,7 @@ void App::render_thread_main()
                 working_list.front()();
                 working_list.pop_front();
             }
-            async_unlock();
+            async_end();
         }
     }
 }
diff --git a/src/app.h b/src/app.h
index dbc3b31..3d98f5a 100644
--- a/src/app.h
+++ b/src/app.h
@@ -178,6 +178,7 @@ public:
     void async_start();
     void async_update();
     void async_redraw();
+    void async_swap();
     void async_end();
     void resize(float w, float h);
     void show_cursor();
@@ -272,7 +273,7 @@ public:
 
     // don't capture a reference to this ptr as the object may be destroyed
     // by the time the task is executed
-    template<typename T, typename R = std::result_of<T()>::type>
+    template<typename T, typename R = void>
     std::future<R> render_task_async(T task)
     {
 #ifdef _WIN32
@@ -294,7 +295,7 @@ public:
 #endif // _WIN32
     }
 
-    template<typename T, typename R = std::result_of<T()>::type>
+    template<typename T, typename R = void>
     R render_task(T task)
     {
 #ifdef _WIN32
@@ -342,7 +343,7 @@ public:
 
     // don't capture a reference to this ptr as the object may be destroyed
     // by the time the task is executed
-    template<typename T, typename R = std::result_of<T()>::type>
+    template<typename T, typename R = void>
     std::future<R> ui_task_async(T task)
     {
         std::packaged_task<R()> pt(task);
@@ -362,7 +363,7 @@ public:
         return f;
     }
 
-    template<typename T, typename R = std::result_of<T()>::type>
+    template<typename T, typename R = void>
     R ui_task(T task)
     {
         std::packaged_task<R()> pt(task);
diff --git a/src/main.cpp b/src/main.cpp
index a404796..40facd0 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -146,7 +146,7 @@ bool async_lock_try()
     return true;
 }
 
-void async_swap()
+void win32_async_swap()
 {
     SwapBuffers(hDC);
     //LOG("swap");