Ionic app using Twilio call/sms API

I am looking for ionic 3 mobile app developer for small proof of concept first. i have database of customers(name,email,mobile number),from App i should be able to see list of customers, then on detail page, it is like chat window where i can send sms/mms and even call to customer number using twilio api. when i call i should see basic dial pad with basic buttons like speaker/mute/disconnect etc.

if customer reply back via sms or call, it must be append as chat thread .

Summary: outgoing and incoming call/sms/mms must we within app.

Please see attached basic sketch.