App Store Marketing
Hire a developer that will take you to the finish line.
The final stage of app development is also vital. Apps are more likely to sell if people can get a good idea of how it works before they fork over the money.
I have 5 years of video editing experience in Final Cut Pro. Using that experience, I'll extract the best use-case scenarios from your app. I'll then use my skills to convert them into a demonstration video complete with relevant captions and effects. Your video can be viewed on the App Store, YouTube, and anywhere else you'd like.