Call recording without connection
With iOS you are not able to do so as of today.

If your carrier provides support for conference calls (you can speak to two people simulataneously), you can call do the following:


Call your voicemail so it picks up your call and starts recording.
On the iPhone keypad press "+ add call" and select the person you want to call.
As soon as the other line rings press the "merge" button.
Inform the person that you are recording him/her.
After the call hang up on both calls.


If you have enabled Visual Voice Mail (VVM) the recorded conversation will be available as a recording in "Phone > Voicemail".

Let me know if this works for you.