After you deploy an app, your users will see it listed along with the other apps in the user hub (www.google.com/a/your domain) when they log in. Most installable applications are available immediately after deployment. In some cases, there may be a delay of up to 24 hours before the application is displayed in the universal navigation bar in Google Apps.

Your users simply click the link for an app to use it:

• If the app opens in the context of your company's Google Apps account (for example, mail.google.com/a/your domain/#inbox), users click the app name.
• If the app requires users to log in to a separate web site, users click the URL for that site.

Most apps are also available from the universal navigation bar that is displayed at the top of the page in each Google App (e.g., in Mail, Calendar, Drive). Click the more link to display a list of additional apps:

Note that you cannot deploy an app to a subset of your users at this time. While a vendor might provide some functionality along these lines, when you enable an app, it is visible to all of your users in the Google Apps universal navigation bar.