Add futures to a com/mod for googlemap for joomla

I need a developper to add more futures to an already made com/mod for joomla to show google maps,add poi, add categories and so on. At the moment we are interested to add "joined categories". What are joined categories? A joined categorie is a categorie that take all needed information, like name of poi (point of interest), latitude, longitude and so on, from a Database outside of joomla DB. Then all information where pick all this information must be write in this categorie. Im looking also for a long term collaboration.