Your answer is google with "difference between oracle dba and oracle apps dba" (without quotes).
Both have their own separate pros and cons, different area of expertise and passion.
You may get couple of good links, read them, try to understand them and think which is best suited to you, your choice, your environment, available resources and your past IT level.
Best of Luck for your career.
Pl also see previous discussions on this topic - https://forums.oracle.com/forums/search.jspa?threadID=&q=APPS+and+DBA&objID=c18&dateRange=thisyear&userID=&numResults=15
You should pursue a career in a field that interests and challenges you personally, otherwise you would be unhappy and you would make your employer unhappy.
I am Commerce graduate and in mid career.
I want to change my career.
Please guide if i intend to become DBA, Oracle app DBA or Oracle DBA
Which will we good for me?
Define "good for me"
Define "Oracle app DBA"
Define "Oracle DBA"
"When I use a word," Humpty Dumpty said in rather a scornful tone, "it means just what I choose it to mean -- neither more nor less."
(Lewis Carroll - Through the Looking Glass)
And so it is with job titles.