Thank you for the quick reply.
Are you available for any custom work:
1. To enable this plugin to work with other provider.
2. A SMS subscription widget in the front-end, where people can enter their name, number and drop-down list to choose a particular group.
I have the documentation API, if you are interested I can mail it to you to have a look. If interested you can let me know how much it will cost.
Thanks,
Sachin
