Methods, systems, program products are described to create a social network based on dynamic interests of users and using ad-hoc networking. A user of mobile device can identify another user who is close by and has similar interests. Dynamic interests of the users can be extracted or identified based on mobile usage, browsing history, places traveled, and other user actions. Users are notified if another user who is similar more than a threshold is present nearby. The system also facilitates communication between users by way of chatting, file sharing, image sharing etc.