Ask HN: Options for in-app advertising in a web app?

I am looking to start monetizing a web-based app with ads. I would like some degree of control over where the apps are displayed and the type of ad content is allowed. Presently, the app is ONLY running as a website so the network needs to support this mode of serving ads.

What networks would be a good starting point to look at? Who are the reputable and established players in this space?

At first glance, Google AdSense does not seem to have the level of control I am looking for.