Restrict Oracle DB Login based on SQL Client being used

We have an application in our organization that is based on Oracle Forms 11g (on Oracle Fusion Middleware/WLS). Users have access to the application through accounts created at the database (i.e. they exist in dba_users). Each user is assigned a specific role based on their area of work and they use the user id to log on to the application. The user may have read/write access to certain functionality in the application and for this their roles have the following permissions-

EXECUTE ANY LIBRARY   
SELECT  ANY SEQUENCE   
EXECUTE ANY TYPE      
EXECUTE ANY PROCEDURE 
UPDATE  ANY TABLE      
SELECT  ANY TABLE      
DELETE  ANY TABLE      
EXECUTE ANY INDEXTYPE 
INSERT  ANY TABLE  

Now we have some users requesting for SQL Client access (i.e. TNS settings) so that they can connect to the DB and perform queries for their research. These business users are ofcourse knowledgeable in SQL but we want to restrict their access based on the type of client they use to log on to the database. Any client other than the application itself, should restrict them to "read only".

Is there a way to achieve this?