Twilio voice call to our app

Hi, We want to add call feature to our app using (WebRTC or Twilio API), so our visitors can call us directly from the app. There is no contact form to fill only press call button to call our contact center directly. How can we Receive a call? we can receive the calls using my mobile number (+6018767xxxx) Example: [login to view URL] (website) Note: our app is cross platform was built using Titanium. Please add read at the beginning of your offer to know you are read this description. Thanks