There are really quite a few alternatives other than Adsense - Media.net, Exponential, Conversant, etc
If you want a full list you can visit Mobile Digital Advertising Companies Database - Thalamus
Media.net, Exponential. If you want a full list (you should really join a network that specializes in your niche), you can visit Mobile Digital Advertising Companies Database - Thalamus
Adsense is the publisher-facing side of the Google Display Network. If you join the Adsense network then advertisers buying on the Google Display Network can serve ads on your site.
Adsense is an Ad Network owned by Google to help publishers monetize their website. Advertisers buying on the Google Display Network can serve ads on your website if you have Adsense.
Basically means they would host all the content on Facebook, since they don't want people clicking out of Facebook to go to the publisher's page (saves a couple seconds).
However, that means a lot of publishers would end of being reliant 100% on Facebook which is a scary idea..
Here is some data about them: AdMedia Advertising Reviews, Ratings, Pricing, Mediakits, Contacts, Traffic, Demographics, Reach, Creatives - Thalamus
we have contacts too and you can reach out directly as well.