The developer recommended that you should contact them in order to renew the application since there is no other form of payment available on their website. You just have to get in touch with them through the Live Chat system and they will over you all the necessary information related to payment method, renew details, and the whole activation procedure.
Use the following link to load the website, then click on the bottom right button on the website to launch the live chat function: http://rtdatafeed.com/payment.html
