By default, your speakers and sponsors are listed alphabetically in the app (by first name, in the case of speakers). There is a way to list speakers alphabetically by last name, but you can also use the Sort Manually option to put your lists into your own custom order.
In any Speakers or Companies module, you can slick the “Sort Manually” button and drag any profile to a new position in the list before saving your changes. After these changes are saved, any new profile you add to that module will not be sorted alphabetically. Instead, new profiles will automatically be added to the bottom of the list.