Most of us like to use the fewest clicks possible to reach any particular application. Google Apps for Domains acts as umbrella for Mail, Docs, Calendar and Sites as well as any apps you have added from Google Apps Marketplace.

When you use SAML to log into Google Apps for Domains, you can still link directly to the underlying apps and it works very well with OneLogin. The URLs are going to look something like this:

 https://mail.google.com/a/mycompany.com/?tab=om#inbox
 https://www.google.com/calendar/hosted/mycompany.com/render?tab=oc&...
 https://docs.google.com/a/mycompany.com/?tab=mo&AuthEventSource...

Once you have logged into Google Apps, go to Mail, Docs, Calendar, Sites and add bookmarks for them in your browser's bookmarks bar. Now, if you click on any of those links, you will be taken directly to them. If you are not already logged into Google Apps, OneLogin will log you in automatically. And if you're not logged into OneLogin either, you will be taken directly to the link you clicked after you have logged in.