I have a phone API to built.
You must gather all the information that the API could offer, such has retreive client phone call.
We need an angular phone apps that will allow us to receive and make call.
When we receive a call we need to be able to check our DB is the client exist, so we need a small square that will show us the client information on the call we receive and once we press the button we will be redirected to the client file.
We have a CRM that we use, so you will have to create a module for that.
So you need to have experience, your code will be double check for the quality of it. You need experience with CI, PHP, Angular, SIP protocol and you need to be able to understand the API has the company does not offer any supprt.
I will provide informations, picture and link for you to complete the work.
Come to chat I will anwser all your questions.
Good luck to all