chat rooms app for android and iphone

I am looking for a development company that can create a chat room app that is a cross platform of android and iphone. Users will be able to open the app, enter a username, join a chat room. A list of other users will be on the right. /shortcuts such as /wink /hug for emotives Users can also private chat other members, send pictures, and also assign a picture to their nickname. I would like over 20 chat rooms with the ability to easily create and remove them. Users must be able to block and report other users. Users will only receive files that they accept. ( A Warning should come with every sent file) users can send direct image from camera or upload from gallery. App may require a server which we will discuss, but if so it will be your responsibility to create and set up. Will require a working manual, support and maintance on glitches for the first few months of release