You need to pay $99 to load the software on any phone at all. That gets you the ability to do live debugging on the device while attached to your Mac, and the ability to do a limited release of signed keys and signed .app packages. These limited releases have a maximum number (100) of users and will expire within a couple months.

So yes, unless you jailbreak you must pay Apple $99 to put software on your own phone, and you'll have to resign and republish it to your own device every few months.

Apple does not want you outside their garden.