mobile app

I am looking to build a mobile p2p network for sharing items. The app needs to be able to know where the phone is located, communicate with another device via sms, or pushing a message via the phone, and communicate the location of the other user and generate directions. Here is the workflow: User 1: broadcasts message to other users in his network or group. User 2: receives message, opens app, and communicates back with User 1: User1: communicates back to user 2... USer 2: receives location and turn by turn directions to locate User 1. User 1 & 2: confirm they found eachother.