add ticketfreetext and articlefreetext to all interfaces

[dwg]

Hello, I am getting a little confused trying to setup freetext for interfaces. I figured this question could help with understanding.

I would like to:
- add a couple fields when creating a new ticket (ex. Windows Username, ComputerName)
- add a couple internal fields to any work done on a ticket (articlefreetext?) (ex. Billable Time, Mileage)

Would someone be kind enough to outline their high-level thought process for a task like this?

I suspect it goes something like:
- Core::TicketFreeText - Create the ticket-level fields
- Core::ArticleFreeText - create the note/article level fields
- Add to the appropriate interfaces so that iPhone app, phone ticket, email ticket etc all see these new fields.
- (this is where I get a confused)

Related to above, no matter what I have tried I can't seem to get ticketfreetext or articlefreetext visible in the iPhone app.

Thanks for any feedback. I'll do my best to update thread with details learned from your advice.

[dwg]

Maybe I should narrow the focus of my question....

How do you enable ticketfreetext and articlefreetext for the iPhone app?

I have enabled with a '1' the freetext items in all of the iPhone subgroups just to test it out:
iPhone::Frontend::Agent::Ticket::ViewClose
iPhone::Frontend::Agent::Ticket::ViewCompose
iPhone::Frontend::Agent::Ticket::ViewMove
iPhone::Frontend::Agent::Ticket::ViewNote
iPhone::Frontend::Agent::Ticket::ViewPhone

But when I open an existing ticket in the iPhone app and click add note I do not see the articlefreetext field.
Also, when I create new ticket in iPhone app I do not see ticketfreetext field.

Thanks again!