Ejabber XMMP Services for iOS App

I'm developing a chat app using Ejabber XMPP for ios. I'm able to connect and Authenticate to the server. i'm able to see online and offline users also. but i have an issue with the below i search alot but not found solutions for that can someone help me on this things asked below:

1. How to upload logged-in user avatar as a display pic.

2. How to a person i'm using below method but it is not adding, i'm using simulator to add the user. if i add in android app it is displaying in my simulator.

   -(void)addUser:(XMPPJID *)jid withNickname:(NSString *)optionalName;

but how to call the above method

3. How to disable account temporarily
4. How to delete account
5. How to share audio/video/photo files in chat
6. How to create a group