Implementing a secure application with the Java Cryptography Architecture

I have previously done similar projects for Carnegie Mellon University where in we developed the social networking app to connect CMU alumnus and current student. The basic idea behind the encryption was encrypting the symmetric shared key using RSA encryption algorithm to facilitate secure network and implementing the user authentication with the help of digital signatures and MAC. The reason for low bid is not my incompetency, but it's because I am new to this freelancing world and I want to build my profile. Please let me know if you are interested. Thank you