diff --git a/tests/frontend/NotificationUtils.test.js b/tests/frontend/NotificationUtils.test.js
new file mode 100644
index 0000000..1da598f
--- /dev/null
+++ b/tests/frontend/NotificationUtils.test.js
@@ -0,0 +1,127 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import NotificationUtils from "../../meshchatx/src/frontend/js/NotificationUtils";
+
+describe("NotificationUtils", () => {
+    let originalNotification;
+    let electronMock;
+    let androidMock;
+
+    beforeEach(() => {
+        originalNotification = globalThis.Notification;
+        electronMock = { showNotification: vi.fn() };
+        androidMock = {
+            getPlatform: vi.fn().mockReturnValue("android"),
+            showNotification: vi.fn(),
+            showIncomingCallNotification: vi.fn(),
+            showMissedCallNotification: vi.fn(),
+            cancelIncomingCallNotification: vi.fn(),
+        };
+        globalThis.Notification = vi.fn(function (title, opts) {
+            return { title, opts };
+        });
+        globalThis.Notification.requestPermission = vi.fn().mockResolvedValue("granted");
+    });
+
+    afterEach(() => {
+        globalThis.Notification = originalNotification;
+        delete globalThis.electron;
+        delete globalThis.MeshChatXAndroid;
+        vi.restoreAllMocks();
+    });
+
+    describe("Electron", () => {
+        beforeEach(() => {
+            globalThis.electron = electronMock;
+        });
+
+        it("showNewMessageNotification delegates to electron", () => {
+            NotificationUtils.showNewMessageNotification("Alice", "hello");
+            expect(electronMock.showNotification).toHaveBeenCalledWith("New Message", "Alice: hello");
+        });
+
+        it("showIncomingCallNotification delegates to electron", () => {
+            NotificationUtils.showIncomingCallNotification("Bob");
+            expect(electronMock.showNotification).toHaveBeenCalledWith("Incoming Call", "Bob is calling you.");
+        });
+
+        it("showMissedCallNotification delegates to electron", () => {
+            NotificationUtils.showMissedCallNotification("Charlie");
+            expect(electronMock.showNotification).toHaveBeenCalledWith(
+                "Missed Call",
+                "You missed a call from Charlie."
+            );
+        });
+
+        it("showNewVoicemailNotification delegates to electron", () => {
+            NotificationUtils.showNewVoicemailNotification("Dave");
+            expect(electronMock.showNotification).toHaveBeenCalledWith(
+                "New Voicemail",
+                "You have a new voicemail from Dave."
+            );
+        });
+    });
+
+    describe("Android", () => {
+        beforeEach(() => {
+            globalThis.MeshChatXAndroid = androidMock;
+        });
+
+        it("showNewMessageNotification delegates to Android bridge", () => {
+            NotificationUtils.showNewMessageNotification("Alice", "hello");
+            expect(androidMock.showNotification).toHaveBeenCalledWith("New Message", "Alice: hello");
+        });
+
+        it("showIncomingCallNotification delegates to Android bridge", () => {
+            NotificationUtils.showIncomingCallNotification("Bob");
+            expect(androidMock.showIncomingCallNotification).toHaveBeenCalledWith("Bob");
+        });
+
+        it("showMissedCallNotification delegates to Android bridge", () => {
+            NotificationUtils.showMissedCallNotification("Charlie");
+            expect(androidMock.showMissedCallNotification).toHaveBeenCalledWith(
+                "Missed Call",
+                "You missed a call from Charlie."
+            );
+        });
+
+        it("showNewVoicemailNotification delegates to Android bridge", () => {
+            NotificationUtils.showNewVoicemailNotification("Dave");
+            expect(androidMock.showNotification).toHaveBeenCalledWith(
+                "New Voicemail",
+                "You have a new voicemail from Dave."
+            );
+        });
+
+        it("cancelIncomingCallNotification delegates to Android bridge", () => {
+            NotificationUtils.cancelIncomingCallNotification();
+            expect(androidMock.cancelIncomingCallNotification).toHaveBeenCalled();
+        });
+    });
+
+    describe("Browser fallback", () => {
+        it("showNewMessageNotification uses browser Notification API", async () => {
+            NotificationUtils.showNewMessageNotification("Alice", "hello");
+            await new Promise((r) => setTimeout(r, 10));
+            expect(globalThis.Notification).toHaveBeenCalledWith(
+                "New Message",
+                expect.objectContaining({ body: "Alice: hello" })
+            );
+        });
+    });
+
+    describe("_isAndroid detection", () => {
+        it("returns false when MeshChatXAndroid is missing", () => {
+            expect(NotificationUtils._isAndroid()).toBe(false);
+        });
+
+        it("returns false when getPlatform returns non-android", () => {
+            globalThis.MeshChatXAndroid = { getPlatform: () => "ios" };
+            expect(NotificationUtils._isAndroid()).toBe(false);
+        });
+
+        it("returns true when getPlatform returns android", () => {
+            globalThis.MeshChatXAndroid = androidMock;
+            expect(NotificationUtils._isAndroid()).toBe(true);
+        });
+    });
+});
diff --git a/tests/frontend/Toast.test.js b/tests/frontend/Toast.test.js
index 95c2bac..ddc3a4d 100644
--- a/tests/frontend/Toast.test.js
+++ b/tests/frontend/Toast.test.js
@@ -99,4 +99,12 @@ describe("Toast.vue", () => {
         const toast = wrapper.find(".pointer-events-auto");
         expect(toast.find("button").exists()).toBe(true);
     });
+
+    it("positions container with mobile-safe bottom offset", () => {
+        const container = wrapper.find("[class*='fixed']");
+        expect(container.exists()).toBe(true);
+        const cls = container.classes().join(" ");
+        expect(cls).toContain("max-sm:bottom-");
+        expect(cls).not.toContain("max-sm:bottom-[calc(5.75rem");
+    });
 });