Mobile Application for making Audio-Video Chat using WebRTC

We need an Experienced Developer to create a Mobile Application for Android phones, for Audio Chat / Video Chat using WebRTC. The Application design and layout should be like WhatsApp or oovoo ([login to view URL]) . The USP of the Application is that Users who download the application can do Audio / Video Chat Like Skype. All users who have downloaded the application can see the other users who are Online and Offline The minutes of useage are to be tracked which means that Customers Pay and get Minutes to consume. The Customer's Minutes can be consumed anytime. The customer can make partial calls and consume minutes in due course as per his wish. Once the Minutes are Consumed then the customer is asked to Buy Minutes Again and he is unable to make Calls. The Rate of Audio Calls and Video Calls will be different. Means That the Minutes are to be tracked properly. The Calls or Minutes tracking or consumption will be 1 for Audio Calls and 1.5 for Video Calls. There has to be complete tracking as to where the minutes were consumed along with time and complete details as to which user consumed how many minutes with which user. Proper Reports are to be Generated. There is to be a Referral or Affiliates Tracking system wherein We need to have a track that the user downloaded the Application from which Affiliate or the User Purchased minutes from which Affiliates website. Accordingly reports are to be generated. There are to be two Billing Integrations from our Billing Partners wherein users can pay the Company to Buy Minutes/Talk Time. The Billing API's will be provided by our Billing Partners and the Developer needs to Integrate the same into our Mobile Application. This is the first Phase of our Project and needs to be Developed on an Urgent Basis. We need a Long term association with the Developer as after this is Completed we need to add many other features like Instant Messaging/Chat/Image-Video Transfer and to create a Dating App.