Best ad network for web-app?

As I have recently unfortunately found out with Ezoic it's irrelevant if website is approved by ad network if after it it isn't approved by Google Ad Manager.
As far as I understand all other bigger ad networks like Mediavine, AdThrive, Monetizemore... depend on monopoly of Google Ad Manager.

So my question is what is the best way to monetize single page web-app, non-dependent on Google?

If it makes any difference it's a simple single-page web app with about 1000 words content on it.
Most ad-networks I googled as alternative to Adsense someone is saying it's a scam.

Anyone have experience with AdMaven or AdCash?