Hi Jeanninem,
With the latest update and changes, the Send & Track service is available via Adobe Reader DC desktop app or Adobe Document Cloud. The service has been upgraded with the name Share & Track.
Is there any specific feature that you are looking for? Because there isn't much that has been changed with the service. You can refer to the help article Adobe Send & Track FAQ where it.
Also, please refer to link Share and track PDFs online using Adobe Document Cloud to see how does it works.
We would be looking forward for an update from you.
Regards,
Akanchha