We want to develop a mobile app platform that users can use videotalk or phonecall to call each other by paying money for these callings. It will be a basic app with a good design. Every user have to enter some informations about himself and approve user agreement to create a profile. After this calling, users will be able to rate the other person out of 5. I want to learn about hosting costs monthly and app development cost, also average development period in terms of week or month. For detailed information, please contact me.