This guide provides an overview of how people start and work with a
Google Meet add-on.

## Start an add-on from the Activities panel

From a Google Meet call, a user can click the Activities button. This brings
up the Activities panel, which shows a list of built-in Meet
features and any add-ons the user has installed. Clicking on an
icon launches the side panel view of the add-on.
![The Google Meet add-ons SDK main stage and side panel.](https://developers.google.com/static/workspace/meet/add-ons/images/meet-add-ons-sdk-framework-definition2.svg) **Figure 1.** The Google Meet add-ons SDK main stage and side panel.

## Collaborate with other users

To allow users to collaborate together, the add-on can
set the
[`ActivityStartingState`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/addon_sdk.activitystartingstate).
For more information, see [Collaborate using a
Meet add-on](https://developers.google.com/workspace/meet/add-ons/guides/collaborate-in-the-add-on).

After opening an add-on, side panel users can start
working together once the add-on invokes the
[`startActivity()`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/addon_sdk.meetaddonclient.startactivity)
method.

For example, an add-on might want to allow users to
collaborate on a document, but the add-on doesn't know
which document. In this case, the document should be selected from the side
panel view. After ensuring the document can be shared with others, the
add-on can set `ActivityStartingState` with other
necessary document identifiers.

## Collaborate in the main stage

Collaborative activities can be done in the side panel or the main stage. If a
`mainStageUrl` is listed in the add-on manifest,
invoking the
[`startActivity()`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/addon_sdk.meetaddonclient.startactivity)
method automatically opens the add-on in the main stage
and starts the activity.

Once the main stage is open, an add-on might choose to
close the side panel by calling the
[`unloadSidePanel()`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/addon_sdk.meetmainstageclient.unloadsidepanel)
method. To extend the earlier example, a side panel that chooses a document may
no longer be relevant and can be closed.

To re-open the side panel view, the add-on can call the
[`loadSidePanel()`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/addon_sdk.meetmainstageclient.loadsidepanel)
method. For example, an add-on that creates user polls
might reopen the side panel to display question response rates.

## Start an add-on from screen sharing

Users can start add-ons while screen sharing. If a user is screen
sharing a website that has an add-on, that website can
promote its add-on to the user by using the
[`exposeToMeetWhenScreensharing()`](https://developers.google.com/workspace/meet/add-ons/reference/websdk/screenshare_api.meetaddonscreenshare.exposetomeetwhenscreensharing)
method. This shows the user a notification banner in the Meet
call, prompting the user to either install or start the
add-on. For more information, see [Promote an
add-on to users through screen
sharing](https://developers.google.com/workspace/meet/add-ons/guides/promote#screen_sharing).

Since additional information can be supplied to the
add-on starting state from the website the user is
screen sharing, the add-on can skip the side panel and
start the activity in the main stage immediately after launching. If the
add-on needs to perform additional steps, like changing
permissions on a document to share, the add-on can
launch into the side panel and follow the flow described in [Collaborate with
other users](https://developers.google.com/workspace/meet/add-ons/guides/use-add-on#collaborate-with-other-users).

## Related topics

- [Collaborate using a Meet add-on](https://developers.google.com/workspace/meet/add-ons/guides/collaborate-in-the-add-on)
- [Promote an add-on to users through screen sharing](https://developers.google.com/workspace/meet/add-ons/guides/screen-sharing)