diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2fb9be9e..9eba304d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -49,6 +49,10 @@
 - on macOS, fix incorrect ReceivedCharacter events for some key combinations.
 - **Breaking:** Use `i32` instead of `u32` for position type in `WindowEvent::Moved`.
 - On macOS, a mouse motion event is now generated before every mouse click.
+- On Windows, `set_ime_position` is now a no-op instead of a runtime crash.
+- On Android, `set_fullscreen` is now a no-op instead of a runtime crash.
+- On iOS and Android, `set_inner_size` is now a no-op instead of a runtime crash.
+- **Breaking:** On Web, `set_cursor_position` and `set_cursor_grab` will now always return an error.
 
 # 0.21.0 (2020-02-04)
 
diff --git a/src/platform_impl/android/mod.rs b/src/platform_impl/android/mod.rs
index d42b9420..e4bdef82 100644
--- a/src/platform_impl/android/mod.rs
+++ b/src/platform_impl/android/mod.rs
@@ -419,7 +419,7 @@ impl Window {
     }
 
     pub fn set_inner_size(&self, _size: Size) {
-        panic!("Cannot set window size on Android");
+        warn!("Cannot set window size on Android");
     }
 
     pub fn outer_size(&self) -> PhysicalSize<u32> {
@@ -441,7 +441,7 @@ impl Window {
     pub fn set_maximized(&self, _maximized: bool) {}
 
     pub fn set_fullscreen(&self, _monitor: Option<window::Fullscreen>) {
-        panic!("Cannot set fullscreen on Android");
+        warn!("Cannot set fullscreen on Android");
     }
 
     pub fn fullscreen(&self) -> Option<window::Fullscreen> {
diff --git a/src/platform_impl/ios/window.rs b/src/platform_impl/ios/window.rs
index ec943116..5fa83e90 100644
--- a/src/platform_impl/ios/window.rs
+++ b/src/platform_impl/ios/window.rs
@@ -142,7 +142,7 @@ impl Inner {
     }
 
     pub fn set_inner_size(&self, _size: Size) {
-        unimplemented!("not clear what `Window::set_inner_size` means on iOS");
+        warn!("not clear what `Window::set_inner_size` means on iOS");
     }
 
     pub fn set_min_inner_size(&self, _dimensions: Option<Size>) {
diff --git a/src/platform_impl/web/window.rs b/src/platform_impl/web/window.rs
index bd525056..58d55135 100644
--- a/src/platform_impl/web/window.rs
+++ b/src/platform_impl/web/window.rs
@@ -171,14 +171,12 @@ impl Window {
 
     #[inline]
     pub fn set_cursor_position(&self, _position: Position) -> Result<(), ExternalError> {
-        // Intentionally a no-op, as the web does not support setting cursor positions
-        Ok(())
+        Err(ExternalError::NotSupported(NotSupportedError::new()))
     }
 
     #[inline]
     pub fn set_cursor_grab(&self, _grab: bool) -> Result<(), ExternalError> {
-        // Intentionally a no-op, as the web does not (properly) support grabbing the cursor
-        Ok(())
+        Err(ExternalError::NotSupported(NotSupportedError::new()))
     }
 
     #[inline]
diff --git a/src/platform_impl/windows/window.rs b/src/platform_impl/windows/window.rs
index 0f4dcf8b..3b8dc98f 100644
--- a/src/platform_impl/windows/window.rs
+++ b/src/platform_impl/windows/window.rs
@@ -609,7 +609,7 @@ impl Window {
 
     #[inline]
     pub fn set_ime_position(&self, _position: Position) {
-        unimplemented!();
+        warn!("`Window::set_ime_position` is ignored on Windows")
     }
 
     #[inline]
diff --git a/src/window.rs b/src/window.rs
index 000adef7..d6b55830 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -401,6 +401,7 @@ impl Window {
     /// ## Platform-specific
     ///
     /// - **iOS:** Can only be called on the main thread.
+    /// - **Android:** Unsupported.
     #[inline]
     pub fn request_redraw(&self) {
         self.window.request_redraw()
@@ -420,6 +421,7 @@ impl Window {
     ///   window's [safe area] in the screen space coordinate system.
     /// - **Web:** Returns the top-left coordinates relative to the viewport. _Note: this returns the
     ///    same value as `outer_position`._
+    /// - **Android / Wayland:** Always returns [`NotSupportedError`].
     ///
     /// [safe area]: https://developer.apple.com/documentation/uikit/uiview/2891103-safeareainsets?language=objc
     #[inline]
@@ -442,6 +444,7 @@ impl Window {
     /// - **iOS:** Can only be called on the main thread. Returns the top left coordinates of the
     ///   window in the screen space coordinate system.
     /// - **Web:** Returns the top-left coordinates relative to the viewport.
+    /// - **Android / Wayland:** Always returns [`NotSupportedError`].
     #[inline]
     pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         self.window.outer_position()
@@ -457,6 +460,7 @@ impl Window {
     /// - **iOS:** Can only be called on the main thread. Sets the top left coordinates of the
     ///   window in the screen space coordinate system.
     /// - **Web:** Sets the top-left coordinates relative to the viewport.
+    /// - **Android / Wayland:** Unsupported.
     #[inline]
     pub fn set_outer_position<P: Into<Position>>(&self, position: P) {
         self.window.set_outer_position(position.into())
@@ -485,8 +489,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Unimplemented. Currently this panics, as it's not clear what `set_inner_size`
-    ///   would mean for iOS.
+    /// - **iOS / Android:** Unsupported.
     /// - **Web:** Sets the size of the canvas element.
     #[inline]
     pub fn set_inner_size<S: Into<Size>>(&self, size: S) {
@@ -513,8 +516,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web:** Unsupported.
     #[inline]
     pub fn set_min_inner_size<S: Into<Size>>(&self, min_size: Option<S>) {
         self.window.set_min_inner_size(min_size.map(|s| s.into()))
@@ -524,8 +526,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Andraid / Web:** Unsupported.
     #[inline]
     pub fn set_max_inner_size<S: Into<Size>>(&self, max_size: Option<S>) {
         self.window.set_max_inner_size(max_size.map(|s| s.into()))
@@ -538,7 +539,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - Has no effect on iOS.
+    /// - **iOS / Android:** Unsupported.
     #[inline]
     pub fn set_title(&self, title: &str) {
         self.window.set_title(title)
@@ -549,9 +550,8 @@ impl Window {
     /// If `false`, this will hide the window. If `true`, this will show the window.
     /// ## Platform-specific
     ///
-    /// - **Android:** Has no effect.
+    /// - **Android / Wayland / Web:** Unsupported.
     /// - **iOS:** Can only be called on the main thread.
-    /// - **Web:** Has no effect.
     #[inline]
     pub fn set_visible(&self, visible: bool) {
         self.window.set_visible(visible)
@@ -570,8 +570,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web:** Unsupported.
     #[inline]
     pub fn set_resizable(&self, resizable: bool) {
         self.window.set_resizable(resizable)
@@ -581,7 +580,8 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect
+    /// - **iOS / Android / Web:** Unsupported.
+    /// - **Wayland:** Un-minimize is unsupported.
     #[inline]
     pub fn set_minimized(&self, minimized: bool) {
         self.window.set_minimized(minimized);
@@ -591,8 +591,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web:** Unsupported.
     #[inline]
     pub fn set_maximized(&self, maximized: bool) {
         self.window.set_maximized(maximized)
@@ -617,6 +616,7 @@ impl Window {
     /// - **iOS:** Can only be called on the main thread.
     /// - **Wayland:** Does not support exclusive fullscreen mode.
     /// - **Windows:** Screen saver is disabled in fullscreen mode.
+    /// - **Android:** Unsupported.
     #[inline]
     pub fn set_fullscreen(&self, fullscreen: Option<Fullscreen>) {
         self.window.set_fullscreen(fullscreen)
@@ -627,6 +627,7 @@ impl Window {
     /// ## Platform-specific
     ///
     /// - **iOS:** Can only be called on the main thread.
+    /// - **Android:** Will always return `None`.
     #[inline]
     pub fn fullscreen(&self) -> Option<Fullscreen> {
         self.window.fullscreen()
@@ -635,9 +636,8 @@ impl Window {
     /// Turn window decorations on or off.
     ///
     /// ## Platform-specific
-    /// - **iOS:** Can only be called on the main thread. Controls whether the status bar is hidden
-    ///   via [`setPrefersStatusBarHidden`].
-    /// - **Web:** Has no effect.
+    ///
+    /// - **iOS / Android / Web:** Unsupported.
     ///
     /// [`setPrefersStatusBarHidden`]: https://developer.apple.com/documentation/uikit/uiviewcontroller/1621440-prefersstatusbarhidden?language=objc
     #[inline]
@@ -649,8 +649,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web / Wayland:** Unsupported.
     #[inline]
     pub fn set_always_on_top(&self, always_on_top: bool) {
         self.window.set_always_on_top(always_on_top)
@@ -661,7 +660,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// This only has an effect on Windows and X11.
+    /// - **iOS / Android / Web / Wayland / macOS:** Unsupported.
     ///
     /// On Windows, this sets `ICON_SMALL`. The base size for a window icon is 16x16, but it's
     /// recommended to account for screen scaling and pick a multiple of that, i.e. 32x32.
@@ -677,8 +676,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// **iOS:** Has no effect.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web / Wayland / Windows:** Unsupported.
     #[inline]
     pub fn set_ime_position<P: Into<Position>>(&self, position: P) {
         self.window.set_ime_position(position.into())
@@ -691,8 +689,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Has no effect.
-    /// - **Android:** Has no effect.
+    /// - **iOS / Android:** Unsupported.
     #[inline]
     pub fn set_cursor_icon(&self, cursor: CursorIcon) {
         self.window.set_cursor_icon(cursor);
@@ -702,8 +699,7 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS:** Always returns an `Err`.
-    /// - **Web:** Has no effect.
+    /// - **iOS / Android / Web / Wayland:** Always returns an [`ExternalError::NotSupported`].
     #[inline]
     pub fn set_cursor_position<P: Into<Position>>(&self, position: P) -> Result<(), ExternalError> {
         self.window.set_cursor_position(position.into())
@@ -713,13 +709,8 @@ impl Window {
     ///
     /// ## Platform-specific
     ///
-    /// - **macOS:** This presently merely locks the cursor in a fixed location, which looks visually
-    ///   awkward.
-    /// - **Wayland:** This presently merely locks the cursor in a fixed location, which looks visually
-    ///   awkward.
-    /// - **Android:** Has no effect.
-    /// - **iOS:** Always returns an Err.
-    /// - **Web:** Has no effect.
+    /// - **macOS / Wayland:** This locks the cursor in a fixed location, which looks visually awkward.
+    /// - **iOS / Android / Web:** Always returns an [`ExternalError::NotSupported`].
     #[inline]
     pub fn set_cursor_grab(&self, grab: bool) -> Result<(), ExternalError> {
         self.window.set_cursor_grab(grab)
@@ -736,8 +727,7 @@ impl Window {
     /// - **Wayland:** The cursor is only hidden within the confines of the window.
     /// - **macOS:** The cursor is hidden as long as the window has input focus, even if the cursor is
     ///   outside of the window.
-    /// - **iOS:** Has no effect.
-    /// - **Android:** Has no effect.
+    /// - **iOS / Android:** Unsupported.
     #[inline]
     pub fn set_cursor_visible(&self, visible: bool) {
         self.window.set_cursor_visible(visible)