Hello Sir,
checkout the "Upicit" application on iTunes. I can give you its link if you need.
I have mostly everything ready developed of what you need. for example, Login, Sign up, Intro screen, Posting Image, Comment, Like, Message, Follower, Followings, Profile page, Home page, search options, Hashtag, etc.
I have that application done in iPhone and Android (not on market yet)
Let me know if you are interested.. .