Hi there,
I have just finished similar web service app where server can send sms to device
free of charge
I can send you the apk file also for demo or screenshot.
But the problem is it work only for android device,i have not worked on other mobile os.
Being starter on freelancer.in,I can assure you for proper service.
I will be glad to help you on your project,I am waiting for your response.
Thanks & Regards,
Anil Kumar