Ask HN: What if we provide an easy way to make your users promote your app

Hi,<p>A friend and I are building mobile apps, (me for iOS, and my friend for Android) we are looking for traction for our apps and we find that if we make our users tell their friends that our app are great it will be awesome. So we might develop the whole stuff for us but I think there might be a market since there are a lot of developer who want to make their app more used. I would like to know if someone is interested in our idea ? Thx