They had an "apps" division because there were entire other companies with reasonably similar market cap at the time (Peoplesoft, Siebel, SAP) who basically wrote apps (and only the apps) as well (they required databases to function but were flexible on DB engine).

Apps are what organizations/people buy. Databases are just the storage engine.

The difference is that Oracle underwrote their apps with database profits and they never got the apps game.