Build tabs for meeting

Every team has a different way of communicating and collaborating tasks. To achieve these different tasks, customize Teams with apps for meetings. Enable your apps for Teams meetings and configure the apps to be available in the meeting scope within their app manifest.

Tabs in Teams meetings

Tabs allow the meeting participants to access services and content in a specific space within a meeting. If you're new to Microsoft Teams tab development, see build tabs for Teams.

Before creating a meeting tab, it's important to learn about the surfaces that are available to target the meeting chat view, meeting details view, meeting side panel view and meeting stage view.

Meeting details view

  1. In your calendar, select a meeting to which you want to add a tab.

  2. Select the Details tab and select . The app gallery appears.

    This screenshot shows the pre-meeting app experience in Teams meeting.

  3. In the app gallery, select the app that you want to add and follow the steps as required. The tab is added to the meeting details page.

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

The screenshot shows desktop Teams tabs in the meeting details view in the Teams meeting.

Meeting chat view

  1. From the Teams chat panel, select the meeting chat view.

  2. Select and the app gallery appears.

  3. In the app gallery, select the app that you want to add and follow the steps as required. The tab is added to the meeting chat.

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

The screenshot shows the meeting chat view in a meeting chat in Teams desktop.

Meeting side panel view

  1. During a meeting, you can select Apps from Teams meeting window to add apps to the meeting.

    This screenshot shows how to add an app in Teams meeting window.

  2. In the app gallery, select the app that you want to add and follow the steps as required. The app is added to the meeting side panel.

    This screenshot shows side panel view with the list of apps.

Meeting stage view

  1. After a tab is added to the meeting side panel, you can now choose to opt into global app sharing.

  2. This results in rendering tab on the stage for every participant in the meeting.

The following image shows a tab added to the meeting stage in the Teams desktop client:

This screenshot shows meeting stage view of the app you shared to meeting in Teams desktop.

Apps in channel meeting

A public scheduled channel meeting has the same list of apps as its parent team. Installing an app to a channel meeting also makes it available in the parent team, and vice versa.

However, the tab instances in a channel meeting are separate from the tabs in the channel itself. For example, suppose a Development channel has a Polly tab. If you create a Standup meeting in that channel, that meeting wouldn't have a Polly tab, until you explicitly add the tab to the meeting.

The following image shows apps in a channel in the Teams desktop client:

This screenshot shows a tab added to a channel meeting in Teams desktop.

In public scheduled channel meetings, after a meeting tab is added, you can select the meeting object in the meeting details page to access the tab.

After a meeting

Note

On mobile, anonymous users can't access apps in scheduled public channel meetings.

App manifest settings for Tabs in meeting

Update your app manifest with relevant context property to configure the different tab views. The meetings app capabilities are declared in your app manifest using the scopes and context arrays under the configurableTabs section.

Scope

The scope defines who can access the apps.

  • groupchat scope makes your app available in a group scope and enables the app to be added in a call or meeting (scheduled private meeting or instant meetings).

  • team scope makes your app available in a team scope and enables your app to be added in team or channel or scheduled channel meeting.

Context

The context property determines if the app is available in specific view after installation and configuration. Following are the values for the context property from which you can use all or some of the values:

Value Description
channelTab A tab in the header of a team channel.
privateChatTab A tab in the header of a group chat between a set of users, not in the context of a team or meeting.
meetingChatTab A tab in the header of a group chat between a set of users for a scheduled meeting. You can specify either meetingChatTab or meetingDetailsTab to ensure the apps work in mobile.
meetingDetailsTab A tab in the header of the meeting details view of the calendar. You can specify either meetingChatTab or meetingDetailsTab to ensure the apps work in mobile.
meetingSidePanel An in-meeting panel opened through the unified bar (U-bar).
meetingStage An app from the meetingSidePanel can be shared to the meeting stage. You can't use this app in Teams room clients.

Configure tab app for a meeting

Apps in meetings can use the following contexts: meetingChatTab, meetingDetailsTab, meetingSidePanel and meetingStage. After a meeting participant installs an app and configures the tab in meeting, all the targeted other contexts of the app for the given meeting starts to render the tab.

The following code snippet is an example of a configurable tab used in an app for Teams meetings:


"configurableTabs": [
    {
      "configurationUrl": "https://contoso.com/teamstab/configure",
      "canUpdateConfiguration": true,
      "scopes": [
        "team",
        "groupchat"
      ],
      "context":[
        "channelTab",
        "privateChatTab",
        "meetingChatTab",
        "meetingDetailsTab",
        "meetingSidePanel",
        "meetingStage"
     ]
    }
  ]

Other examples

Default context for tabs (if not specified) is: 

"context":[ 
  "channelTab", 
  "privateChatTab", 
  "meetingChatTab", 
  "meetingDetailsTab" 
     ] 

To prevent an app from showing in non-meeting group chats, you must set the following context:

"context":[ 
  "meetingSidePanel", 
  "meetingChatTab", 
  "meetingDetailsTab" 
     ] 

For in-meeting side panel experience only: 

"context":[ 
  "meetingSidePanel" 
     ] 

Advanced tab APIs

TeamsJS is a rich library used to create Tabs using JavaScript. Use the latest TeamsJS (V.2.0 or later) to work in Teams, Microsoft 365 app, and Outlook. For more information, see Teams JavaScript client library.

Frame context

Microsoft Teams JavaScript library exposes the frameContext in which your meeting tab URL is loaded in the getContext API. The possible values of frameContext are content, task, setting, remove, sidePanel, and meetingStage. This allows you to build customized experiences based on where the app renders. For example, showing a specific collaboration focused UI when in the meetingStage and a different meeting preparation UI in the chat tab (content). For more information, see getContext API.

App caching

App caching improves subsequent launch time of the apps that are loaded in the meeting side panel by allowing you to keep some resources and assets in memory that you can use when rehydrating app.

Note

  • App caching is available only in public developer preview.
  • App caching is supported only for tabs loaded in the meeting side panel in Teams desktop client. While it can work in other contexts such as personal apps and chat or channel tabs, it isn't officially supported. We recommend to register the onLoad or beforeUnload handlers when in the sidePanel frameContext.

Enable app caching

To enable app caching in your meeting side panel, follow the steps:

  1. Call teamsCore.registerBeforeUnloadHandler and teamsCore.registerOnLoadHandler APIs.

  2. Use contentUrl and entityId passed into the load handler to route to the correct page within your app and invoke notifySuccess or notifyFailure to notify Teams client that the app initialization flow is complete.

  3. Dispose resources and perform any cleanup needed in the beforeUnload handler, then invoke the readyToUnload callback to notify Teams client that the app unload flow is complete.

The following is the flow diagram of the first launch of an app that wants to opt into app caching (register the load or beforeUnload on the first launch of the app):

This screenshot shows the flow of the first launch of the app in meeting side panel.

The following is the flow diagram of the launch of cached app:

This screenshot shows the flow of the cached launch of the app in meeting side panel.

When you opt into app caching, the webview that is used to host the embedded app is reused as users navigate to different instances of the app within a window. The webview used to host the app is hidden when the users leave the app and shown when the users return to the app. When the app is cached, any audio that is playing is muted.

Note

If the app caching isn't enabled, the webview is recreated every time the user launches the app.

There are multiple reasons for an app to not get cached or for an app to get removed from the cache, some of the reasons are (numbers here are subject to change):

  • If the system memory load is high, the app is removed from the cache.
  • If the number of cached apps exceed the maximum cache size, the oldest cached app is removed from the cache.
  • If the user doesn't return to the app within 20 minutes, the app is removed from the cache.
  • The app isn't cached if Teams doesn't receive the readyToUnload signal from the app within 30 seconds after sending the beforeUnload notification.
  • App caching is disabled if the system memory is less than 4 GB or if the available memory is less than 1 GB on Windows or 512 MB on Mac.
  • Side panel is the only supported frameContext for app caching in meetings.
  • App caching isn't supported for meetings where the invited user count is more than 20.
  • If an app fails to load, the app isn't cached.

Code example

The following code snippet is an example of teamsCore.registerOnLoadHandler and teamsCore.registerBeforeUnloadHandler APIs:

microsoftTeams.teamsCore.registerOnLoadHandler((data) => {
    console.log("got load from TEAMS", data.contentUrl, data.entityId);
    // use contentUrl to route to correct page 
    // invoke notifySuccess when ready  
    app.notifySuccess();
});

microsoftTeams.teamsCore.registerBeforeUnloadHandler((readyToUnload) => {
    // dispose resources and then invoke readyToUnload
    readyToUnload();
    return true;
});

Limitations

The following are the limitations for app caching:

  • Single-page apps that use client-side routing for page navigation can benefit from app caching. It's recommended that the same domain be used across all contexts of your app launch.

  • Apps need to re-register for events such as themeChange, focusEnter, and so on, in the load handler. Teams client won't send any notifications to the app when cached. If your app requires notifications even when cached, caching might not be the right solution.

  • App caching is supported only in Teams desktop client. In Teams web client, even if the app registers load handlers, the app is removed from the cache after the unload sequence is completed.

  • Register the load and beforeUnload handlers early in your launch sequence. If the Teams client doesn’t see these registrations before the user leaves the app, the app isn't cached.

  • The Teams client invokes the loadHandler only after the unload sequence of the app is completed. For example, if a user launches tab A of your app and then launches tab B of the same app, tab B won't get the load signal until the tab A invokes the readyToUnload callback.

  • Apps are cached on a per-window basis. App caching happens on a per app (not on a per tab) basis within the same window.

  • App caching isn't supported for the meeting stage or Task module contexts, because these can be opened on top of the tab and the same webview can't be used to render the content in the tab and the Task module.

  • Register only the beforeUnload handler if your app doesn't require app caching but needs time to safely save state (as leaving the app can cause the app content to be abruptly removed from the Document Object Model (DOM)). If the app hasn't registered for the load event, it's removed from the DOM after the unload flow completes.

  • Follow the guidelines in this section to onboard your app to app caching in Teams meeting. For app caching support only in meetings, register the load or beforeUnload handlers if the context is sidePanel.

  • Apps are expected to sleep when cached (use minimal compute or network resources and minimizes SDK requests). All the register handlers and the following SDK requests are allowed when the app is cached:

    • initialize
    • notifyappLoaded
    • notifySuccess
    • notifyFailure
    • notifyExpectedFailure
    • getContext
    • getAuthToken
    • readyToUnload
    • getConfig/getSettings

Troubleshooting

Apps are not being cached? Why is load handler not invoked on subsequent navigation?

  • Verify if the system and available memory constraints are met.

  • Reduce your memory footprint when cached. Use the beforeUnload handler to dispose resources, for example, release references and remove event listeners, that might not be needed when cached.

Feature compatibility by user types

The following table provides the user types and lists the features that each user can access the tabs in meetings:

User type Scheduled meeting or Instant calendar meeting One-on-one call Group call Scheduled channel meeting
In-tenant Interaction allowed for all roles.

Create, update, or delete is allowed for all except the Attendees.
Interaction and create, update, or delete allowed.

In-tenant users in call with federated users can't interact and create, update, or delete.
Interaction and create, update, or delete allowed.

In-tenant users in call with federated users can't interact and create, update, or delete.
Interaction and create, update, or delete allowed for all roles except for attendees.
Guest Can interact only Can interact only Can interact only Can interact only.
Federated or External Can interact only Not available Not available Can interact only
Anonymous Not available Not available Not available Not available

Code sample

Sample name Description .NET Node.js
Meeting app Demonstrates how to use the Meeting Token Generator app to request a token. The token is generated sequentially so that each participant has a fair opportunity to contribute in a meeting. The token is useful in situations like scrum meetings and Q&A sessions. View View
Meeting stage sample Sample app to show a tab in meeting stage for collaboration. View View
Meeting side panel Sample app to show how to add agenda in a meeting side panel. View NA
In-meeting notification Demonstrates how to implement in-meeting notification using bot. View View
In-meeting document signing Demonstrates how to implement a document signing Teams app. Includes sharing specific app content to stage, Teams SSO, and user specific stage view. View NA
App caching Sample app to show how app caching works in the meeting side panel. NA View

Note

  • Meeting apps (side panel and meeting stage) are supported in Teams desktop and mobile clients.
  • Meeting apps (side panel and meeting stage) in Teams web client is supported only when the developer preview is enabled.

Step-by-step guides

See also