Make sure you have the correct user criteria and put some real effort in the design.  And within your Knowledge Bases, use the correct categories. That will help a lot. Remember that you can put categories in categories! The question we can't answer is what knowledge you put in there. If you don't want an article per application/service, what is it that you are going to document? You can make a group of service owners that is (combined) responsible for the articles, but if I own several communication services and I get notifications on payroll applications, I will be annoyed. 

And be aware that you can link articles to config items. That can help in filtering for the owners (kb_knowledge.cmdb_ci.owner is dynamic me)