You can refer to wordpress EasySMS plugin for souce code and implementation details. Most of the code would be same except the way it connect to sms gateway. The main features we are looking for are as follows.
1. People should able to register (subscribe feature in EasySMS plugin) and verify their phone no.
2. All verified user can send free sms to india using http post to bulk sms gateway.
3. Option to prefix / suffix a sms that one user send.
4. Way to group users.
5. Site admin should able to send sms to groups.
6. A send sms widget with embed code so that send sms widget can be placed on other sites. iframe widget is also fine.
7. Send widget sms should ask user to register before they can send free sms. This workflow can be done using jquery dialog box.
8. Way to add sms credit to user. User would be able to send sms if they have sms credit.
14 freelancers are bidding on average $495 for this job
Hi! I am really interested in taking up the project. I have the requisite experience and the expertise to complete this project with success. Please view my PM for details. Thanks. Regards. GLOBAL TECHNOSYS
Hi, pls seek no further. Chosen is here for you. I've completed a lot projects in this [url removed, login to view] me for the solution. Waiting for your response.... Thanks