We use this on http://www.skincarebysuzie.com , we tried most of the other SMS notification apps most seem to work well but we wanted the Twilio integration this app provides We do a lot of business over SMS these day, we take order, make appointment, have them funnel into our help desk via our Twilio number, So the problem we had with other service was when a customer responds to our notification asking for help, You have no way to receive it and not answering your customers is never good. so by using our twilio number with this app if they reply to the notification it goes straight to our help desk. I read the negative reviews below and don't understand how they apply to this app, I do not even see where you could buy anything. Add our Twilio number was easy. Had one question customer support answered in a timely manner.