APEX how to link the wwv_flow_fnd_user to the v$session

To get the workspaces I would query the dba_user views.

select username, user_id from dba_users where username like 'APEX%' order by username;
USERNAME                     USER_ID
------------------------- ----------
APEX_030200                      190
APEX_LISTENER                    262
APEX_PUBLIC_USER                 170
APEXSYSUSER                      280
APEX_REST_PUBLIC_USER            263
APEX_040100                      216
APEX_LISTENER_USER               217
APEX_050000                      223                   
APEX_210100                      279                  <--

Then with that result I would use it to the APEX table wwv_flow_fnd_user

select user_id, user_name from APEX_210100.wwv_flow_fnd_user; 

   USER_ID USER_NAME
---------- ----------------------------------------
0015941536 APEXME
9454048894 USER1
8043592063 USER2

Question is how do I link this apex user_id to the v$session so we know who is currently active and what queries or process the apex users are running. Thanks.