hi everybody, I have a project. This project auto Sending SMS. But I but I do not know too much about this subject. I development Java & Android.

for example,passing in front of a shop, will automatically come to the phone, which will assure that this information about shop discounts.

Wish you, What are the requirements to do this project.Do I need additional hardware?How can I do this with GSM carriers? Or how else can carry out a method.
Can you give me some information? Please..

Thank you Everyone...