Xcode hook up with Unity

Hi i am new bee in Unity but i have 1 year experience in Xcode, I am doing an app in Unity for iPhone but getting bit confuse on how can i hook-up Xcode with Unity, I want to Facebook sharing, Twitter Sharing and also iOS native Email sharing(Using Mail Composer) in Unity but i don’t get any help ful solution to do task in Unity, I only get Plugins which i need to Purchase first. So i want to do this task in Xcode it reduce and time and money and rest of work on Unity so is this possible that we can Communicate between Xcode and Unity? If Possible then kindly share some knowledge and links with me so that i can do this task ASAP. Thanks in Advance.

It is definitely possible.

I once worked on a Facebook plugin for iOS and integrated it with Unity. You need to code your stuff in Objective C and provide an interface that can be used in Unity. You can follow the instructions to do this in this thread (also how we did it).

However, I strongly advise you to not follow this approach. If you implement everything in Unity it will be easier to develop, debug and to deploy to different platforms.

In our case, as soon as the new Facebook SDK came out, we changed our project to use it - it makes everything a LOT simpler.