Calling someone on the phone

Calling someone on the phone
 

What is the more appropriate way to say "I am calling Juan"?:thinking:

Estoy llamando a Juan
or
Llamo a Juan

Both are correct. The first makes use of the present progressive tense, which is only used when in the very act of doing something. Do not overuse it. It means I'm in the very process of calling Juan.

The second can mean any of the following:
I call Juan.
I do call Juan.
I'm calling Juan.
I'll call Juan (very shortly).