gmail integration in ios application

Question

I am working on an ios Application, recently I have got a new requirement for it i.e. to provide user a option to sign in with gmail . when user hit the sign in button then

Answer 1

I found it. but then i am just able to fetch the snippet i.e first few words of e-mail body & not the whole . I just stopped coz i did not found any other way to do so. because i am using OAuth 2.0 .