Calling a phone from Xojo-App on a Mac?

Following these instructions, I manage to make phone calls from contacts on my Mac via iPhone.

We have CRM written in Xojo with all the contact info in it and I wonder if there is a way to call or receive phone calls in a similar way as described above?
Is there a plugin or declares to be able to invoke a phone call on a iPhone?

Ideally, if I have the customer information in front of me, I click on a button next to the customers phone number and the iphone will dial.

Or the other way round: When my iphone is called, I can retrieve the phone number on my Mac and search and display all information about the person calling.

If this already works with contacts, there should be a way to achieve this also from a Xojo program, isn’t it?

One way which already works, is using showurl:


Just tel: instead of http: or mailto:

But this does not solve my other question: How can I retrieve the phonenumber on my Mac, when I receive a call?