Do contract work and let others deal with monetization. The problem with creating a mobile ad network is that you're competing with Facebook and Google[0,1]:
> • Facebook and Google have the most inventory and are still growing in terms of both users and ad-load; there is no temporal limitation that works to the benefit of other properties (and Facebook in particular is ramping up efforts to advertise using Facebook data on non-Facebook properties)
> • It is cheaper to produce ads for only Facebook and Google instead of making something custom for every potential advertising platform
> • Facebook and Google have the best tracking, extending not only to digital purchases but increasingly to off-line purchases as well
> • Facebook and Google have the most inventory and are still growing in terms of both users and ad-load; there is no temporal limitation that works to the benefit of other properties (and Facebook in particular is ramping up efforts to advertise using Facebook data on non-Facebook properties)
> • It is cheaper to produce ads for only Facebook and Google instead of making something custom for every potential advertising platform
> • Facebook and Google have the best tracking, extending not only to digital purchases but increasingly to off-line purchases as well
0. https://stratechery.com/2016/the-reality-of-missing-out/
1. https://stratechery.com/2016/how-facebook-squashed-twitter/