-# [Desktop](#tab/desktop)

- The following image shows a tab added to the meeting details page in the Teams desktop client:

- :::image type="content" source="~/assets/images/apps-in-meetings/premeetingtab.png" alt-text="Screenshot shows desktop Teams tabs in the meeting details view in the Teams meeting.":::

-# [Mobile](#tab/mobile)

- The following image shows a tab added to the meeting details page in the Teams mobile client:

- :::image type="content" source="../assets/images/mobile-tab.png" alt-text="Screenshot shows mobile Teams tabs in the meeting details view in the Teams meeting.":::

-# [Meeting chat view desktop](#tab/meeting-chat-view-desktop)

- The following image shows an app added to the meeting chat in the Teams desktop client:

- :::image type="content" source="../assets/images/apps-in-meetings/meeting-chat-view.png" alt-text="Screenshot shows the meeting chat view in a meeting chat in Teams desktop.":::

-# [Meeting chat view mobile](#tab/meeting-chat-view-mobile)

- The following image shows an app added to the meeting chat in the Teams mobile client:

- :::image type="content" source="../assets/images/apps-in-meetings/meeting-chat-view-mobile.png" alt-text="Screenshot shows the meeting chat view in a meeting chat in Teams mobile.":::

-You can show rich unfurl previews of your links without installing your app in Microsoft Teams. Add the [schema.org metadata](https://schema.org/docs/gs.html) to your website in the [JASON-LD format](https://json-ld.org/) and use the micro-capability templates <! link to GitHub templates to be added after the PM shares the public link --> that match your product. Teams uses these templates to unfurl rich previews for your links in Microsoft Teams.

-1. Add the [schema.org](https://schema.org/) metadata with the [JASON-LD format](https://json-ld.org/) to your website.

-The following response is the configuration response appears when the user interact with the compose extension:

-#### Teams-only apps

-Even if you intend your app to only run in Teams (and not Microsoft 365 app and Outlook), best practice is to start referencing the latest TeamsJS (*v.2.0* or later) as soon as convenient, in order to benefit from the latest improvements, new features, and support (even for Teams-only apps). TeamsJS v.1.12 will continue to be supported.

-Once you're able, the next step is to [update existing application code](#2-update-teamsjs-references) with the changes described in this article. In the meantime, the v.1 to v.2 API translation layer provides backwards compatibility, ensuring your existing Teams app continues to work in TeamsJS version 2.0.

-To implement logic that runs your app in Teams, use the following code snippet:

-```js

-// Ensure that you initialize the TeamsJS once, regardless of how often this is called.

-let teamsInitPromise;

-export function ensureTeamsJSInitialized(){

- if (!teamsInitPromise) {

- teamsInitPromise = microsoftTeams.app.initialize();

- }

- return teamsInitPromise;

-}

-// Function returns a promise which resolves to true if we're running in Teams

-export async function inTeams(){

- try {

- await ensureTeamsJSInitialized();

- const context = await microsoftTeams.app.getContext();

- return (context.app.host.name === microsoftTeams.HostName.teams);

- }

- catch (e) {

- console.log(`${e} from Teams SDK, may be running outside of Teams`);

- return false;

- }

-}

-```

-You must wait for the [app initialization](/javascript/api/@microsoft/teams-js/app#@microsoft-teams-js-app-isinitialized) to complete before proceeding with the function call in order for the app to function correctly. Any program logic designed only for Teams might not function correctly on other Microsoft 365 applications. To ensure the smooth operation of your app across Microsoft 365, make provisions for the logic handling of other Microsoft 365 applications.

-The host name where your app operates is revealed as a *hostName* property on the Context interface (`app.Context.app.host.name`). You can query this at runtime by invoking `getContext`. For the previous Teams client, this value might return as *unknown* or *undefined*. In such cases, map these values to old Teams.

- * Messaging extension

-> CodeLens to trigger Teams Toolkit lifecyscle, Teams Toolkit documentation and Copilot plugin is available in public developer preview.