Call external VOIP api from within a lead/contact

[galvinfreeman]

I want to call an external VOIP api when a crm user clicks a "Call" button from with a lead / contact.

1. The VOIP tool I'm integrating with isn't in espo's supported VOIPs so I need to call an api.
2. I need to have a good visual experience where I inform the crm user that the call is being made.

Here's what I tried:
1. Build a manual workflow that calls the external api when a button is clicked inside the lead page: this technically calls the external api but the UI experience isn't very good. It just shows a "Done" message to the user.
2. I tried using a WYSIWYG field but this doesn't allow me to call apis, as far as I know.

Any recommendation on how to acheive this?

[item]

Hi,
do you have API documentation ?
have you somes skill in development ? front-end and back-end (basic skill)

This can help community to respond better