Bulk SMS Platform

A Mobile Marketing company is looking for an easy to use SMS platform with all the latest features. These are not hard to find, so I need someone that has already built an efficient one in the past, so that I can just make slight modifications to it. It should offer the following: 1) SMS Campaigns 2) Auto Responders 3) Bulk SMS 4) SMS Scheduling 5) Payment Gateway Once again, we are looking for completed platforms. Please contact us with your fixed price for these two products, if you don’t have a completed platform, ready-to-go, please don’t bid. Please also reply with links to past completed similar projects. Looking to close this project quickly. Thanks