One more approach that you can follow:

1. Zero out your target location,

2. Go to fiverr.com -> Advertising -> Flyers and Handouts.

3. Choose a person providing a gig at your target location at some school, university or a public place.

4. Make a nice flyer using GIMP or photoshop with your app details and a QR code to download the app.

5. Have him/her use this flyer for distribution.

   I have used it for my app and it has worked to acquire location based app users.

For more details you can contact me. Email address in my profile.