Hi there,
I understand that your requirement is to interface SIM900A GSM Modem With Arduino.
I would like to offer you my service for delivering this project. I have two years of experience in developing software and hardware. I have experience of working on Tegra TK1, TX1, Arduino, AVR, PIC, ARM and Raspberry Pi.
The following are some of the projects that I undertook:
Electronics projects:
1. Quadcopter flight controller and remote controller using AVR ATmega328P microcontroller and Xbee module
2. Self driving car for Mahindra driverless car challenge using openCV libraries, Motion Planning Algorithms, ROS, Python, C++ and Google Map APIs.
3. Live Streaming Servers for a leading car company in India using Tegra TK1, Gstreamer and nginx.
4. Drone Live streaming Server Solution using Tegra TK1,Gstreamer, ffmpeg and nginx server.
5. Drone obstacle avoidance platform.
6. A Number of Android Hardware Interfacing Apps with custom UI Requirements.