Hello Nikola, We are interested in adding our own SMS http api function to EasyAppointments. Advantage of this, for us and possibly other users in our region would be a much lower SMS rate from Twilio and support for geographical sender numbers for our region. We are based in Serbia and we are working with all the major telecom providers in the region. If we provide you with our SMS api documentation, would you be interested in adding a such function to Easy Appointments? Our SMS service will work in Serbia and neighboring countries. If you are willing to give us your thoughts on this and think it would be possible, we are of course, willing to pay for this customized SMS function development. Can we contact you privately anywhere? Regards, Zoran