Appnext has been on the mobile space almost since it started. They have enormous reach and volume across the globe and they are have tremendous coverage of tier 1 countries.
What do you dislike?
Their targeting options are limited. You dont get to granularly choose a lot of variables. Also, they dont track creatives impression which is a really bad practice when you want to optimize.
Recommendations to others considering the product
I have been working with Appnext for the last 4+ years. They are trying to evolve the product to improve their targetting capabilities. I would wait and see if they manage to pull it off before working with them.
What business problems are you solving with the product? What benefits have you realized?
With Appnext I am able to increase my reach and deliver results on my campaigns in order to increase the downloads I can get for my app.
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