Both the above services are offered that you decide to help you with your application should you not desire to control your own application. Foreign nationals must pick a particular aim of travel when completing their on-line application forms. The form is precisely the same for all jurisdictions, though you may want to indicate your particular jurisdiction.
You have to make your primary application online (visa.mfa.gov.ua). Don't forget, after you save and confirm your application, you can't make any further alterations. It also has a series of security questions that must be answered before submitting it.