Hi Marco,

 >
> For example: I want to make a call. I need to enable the modem first or
> I can just dial the number?
> It is just an example to explain my difficulties to understand how to
> use ofono!
>

There isn't an in-depth tutorial available unfortunately.  If someone 
wants to contribute it to the project, that would be appreciated.

Modem must be powered & online in order to make calls.

So roughly:

test/enable-modem
test/online-modem
test/dial-number
test/hangup-call

Regards,
-Denis