Build an encrypted android messaging application

MANDATORY REQUIREMENTS Authentication ● The system has to provide a sign up and sign in system that it uses to authenticate users upon login ● Client to client authentication should be provided ● Upon change of already established session key or RSA key pair, clients should be alerted. ● Authentication should not require user input and should be automatic Encryption ● One on one chats between clients should be provided ● Group chats should be encrypted ● Symmetric keys should be exchanged in a secure manner ● Encryption and decryption of messages should not involve the users ● Individual chat data should be stored on the client machine ● Local chat storage should be encrypted with a different secure algorithm Navigation ● The client end application should be user friendly and be easy to use to new users. A seamless flow of operation should be implemented. ● Navigation between one on one chat and group chat menus should be smooth. Performance ● Encryption and decryption processes should not take up more than recommended system resources ● Latency of messages should not be experienced as IM applications are meant to be real time applications ● System should self-synchronize on start OPTIONAL REQUIREMENTS ● The applications should support multiple languages and have different design choices for users ● Ability to delete chat history and other items can be implemented.