How to get the last access time for specific user in MS CRM 2015?
There is no way directly through front end. You can query database to get the details. Use below query and execute it into your Organization database.
SELECT suo.crmuserid, su.domainname, suo.LastAccessTime
FROM MSCRM_CONFIG.dbo.SystemUserOrganizations suo inner join systemuser su on suo.CrmUserId = su.systemuserid