diff --git a/homeassistant/components/vizio/media_player.py b/homeassistant/components/vizio/media_player.py
index db0282b1d1d3..d9b1f635061b 100644
--- a/homeassistant/components/vizio/media_player.py
+++ b/homeassistant/components/vizio/media_player.py
@@ -208,12 +208,17 @@ class VizioDevice(VizioEntity, MediaPlayerEntity):
                     else ()
                 ),
             )
-            # find_app_name returns None on a catalog miss; the app_name state
-            # attribute contract expects the UNKNOWN_APP sentinel instead
+            # A catalog miss only warrants the UNKNOWN_APP sentinel on the app
+            # input; HDMI and the like report a config that is never an app.
             if app_name == NO_APP_RUNNING:
                 self._attr_app_name = None
             elif app_name is None:
-                self._attr_app_name = UNKNOWN_APP
+                self._attr_app_name = (
+                    UNKNOWN_APP
+                    if self._current_input is not None
+                    and is_app_input(self._current_input)
+                    else None
+                )
             else:
                 self._attr_app_name = app_name
 
diff --git a/tests/components/vizio/test_media_player.py b/tests/components/vizio/test_media_player.py
index 0385be4c6348..4c510c433cc6 100644
--- a/tests/components/vizio/test_media_player.py
+++ b/tests/components/vizio/test_media_player.py
@@ -855,14 +855,45 @@ async def test_apps_update(
                 assert len(apps) == len(APP_RECORDS)
 
 
+@pytest.mark.parametrize(
+    ("entry_data", "app_config", "expected_app_name"),
+    [
+        pytest.param(
+            MOCK_USER_VALID_TV_CONFIG,
+            UNKNOWN_APP_CONFIG_OBJ,
+            None,
+            id="unknown_config_hides_app_name",
+        ),
+        pytest.param(
+            MOCK_TV_WITH_ADDITIONAL_APPS_CONFIG,
+            CUSTOM_CONFIG_OBJ,
+            ADDITIONAL_APP_CONFIG["name"],
+            id="additional_config_keeps_mapped_name",
+        ),
+    ],
+)
 @pytest.mark.usefixtures("vizio_connect", "vizio_update_with_apps_on_input")
 async def test_vizio_update_with_apps_on_input(
-    hass: HomeAssistant, mock_tv_config_entry: MockConfigEntry
+    hass: HomeAssistant,
+    entry_data: dict[str, Any],
+    app_config: AppConfig,
+    expected_app_name: str | None,
 ) -> None:
-    """Test a vizio TV with apps that is on a TV input."""
-    await setup_integration(hass, mock_tv_config_entry)
+    """Test a vizio TV with apps that is on a TV input.
+
+    The device reports an app config even on HDMI. An unrecognized one must
+    not surface as the unknown-app sentinel, while a name mapped through
+    additional_configs is deliberate user configuration and is kept.
+    """
+    config_entry = MockConfigEntry(domain=DOMAIN, data=entry_data, unique_id=UNIQUE_ID)
+    with patch(
+        "homeassistant.components.vizio.Vizio.get_current_app_config",
+        return_value=app_config,
+    ):
+        await setup_integration(hass, config_entry)
     attr = _get_attr_and_assert_base_attr(hass, MediaPlayerDeviceClass.TV, STATE_ON)
-    # app ID should not be in the attributes
+    assert attr[ATTR_INPUT_SOURCE] == CURRENT_INPUT
+    assert attr.get("app_name") == expected_app_name
     assert "app_id" not in attr