should i integrate my webapp with facebook

should i integrate my webapp with facebook

hi my first post (excited! :) ) so i want to write a social web app, which
can be accessed from both ios,android devices as well. my main at the
moment as aproching the "social" thing is why not integrate it in
facebook? tried looking in here and other places, but i cant find any
place with specific answers of what i can and cant do on other sides (pros
and cons of integrating it with facebook or not) without getting too deep
in the applications roll, it do have to hold DB's such as users,their
locations, optional billing now/or in the future, and events of other
sorts.
my questions for now are these: 1. how to check (cuz i couldnt find on my
own) whether its worth integrating my app with facebook or doing it stand
alone 2. where/how to check what options i get from facebook sdk? for
example, if i defined my need for databases, what options do i have with
facebook on this matter?
thanks...