How did you guys manage to hook your first early adopters? I'm considering offering an incentive to get people to use my app. The idea is that these users will stick with my app long-term and will tell their friends and family about it as well, which is free advertising. Of course, it might not work out this way. I guess that's the risk part, because it could result in throwing money down the drain if the users don't like the app or already have a better option.

Well, there's not much of a difference between offering an incentive and paying for advertising. You're paying out money not knowing what your ROI will be. It's a risk we all take, so we set a budget for it.

To answer your question though, I would hook my first adopters through advertising. I can be quite creative.