What do you want your mobile application to do? GT-540P can be used in mobile applications for monitoring and control. The link I provided below shows a video that explains how you can use GT-540P in mobile applications. It is a configurable solution that comes with a software setup utility. You can also develop software on a PC and interact with it. The required power input is 10 - 30 VDC. Please give me your contact information if you want volume pricing.
GT-540P: $679.00 Wireless Intelligent GPRS Remote Terminal Unit with GPS and 2G micro SD card for remote monitoring applications. Ideal for Vehicle Tracking. Has 6 DI, 2 DO, and 1 AI
We also have cellular modems. What data do you want to get back?
Cellular Modems and Routers: http://www.icpdas-usa.com/gsm_modems.html
ICP DAS USA, Inc.
1-888-971-9888 ext 105
We may be able to help you with M2M hardware where you can develop your application. This may be a cost effective approach as you need to focus only on your application and you can reduce time to market.