What's the service? If it's a local one, you're way better off doing it in a market that you are familiar with (your hometown). Not sure what you really mean by "not known for startups" and that shouldn't matter. If your app provides a useful service, people will use it.

There are many other unknowns launching in a city you are entirely unfamiliar with, especially if you have to move there.

It comes back to what the app actually does. Do you have to be in the city to launch it? Is there an offline component of it? If the answer is yes, stay home.