I am the owner of a Mobile Apps development Company. We have developed more than 200 apps till now for our clients. While working and seeing our clients make money with apps, this is what I can summarize for making money for free B2C apps:

Before that, I assume that your app fulfils the following criteria:
1. Satisfies a need. Need can be any task which can be done on the go.
2. App has UI which is simple to understand and does not require you to provide "image overlays" to explain what the app does.

There are two steps to make money:
1. Get more downloads
2. Then make a pitch.

1. Get more downloads:
* Don't plan to put all features in single update. Split it into multiple updates and update the app regularly, make be once a week. This way your app will keep coming in latest apps section on the appstore. I am sure you would have noticed an uptick in downloads in days following the release of your app.

2. Make a pitch
* Find out the general profile of your users. Knowing this you will have fair idea about their needs. Now, find providers who can fulfil their needs.

If nothing works, put your app as paid app at a higher price, say $4.99 or $6.99. I have seen people make good money using this strategy too.

Without knowing what your app is, that is all I can say.

If you have any questions, please feel free to call or email me.

Good luck!

Priyadarshan Joshi
CEO
TaxSmart Technologies Pvt. Ltd
pjoshi@itaxsmart.com