Thank you Nikola for your reply. Can the system send SMS notification automatically, say 30min before their appointment? Or I have manually click certain button do send SMS notification? I am a website builder. I build websites for small retailers. Some of my clients want to have an online booking system with SMS notification to send to their customers 30min before their appointment. Do you have discounts for website builders like me since I will buy a lot of your plugin extensions. Thank you