Originally Posted by CjTheFish

Another one I'd recommend is Wp-Insert. Allows you to do the same but also allows you to create Shortcodes and paste the code directly in the theme to display ads. Useful for if you have a few sites that don't provide a widget under the post/after the content.

The plugin also allows you to set which device type to display it on (mobile/desktop/tablet) and allows you to target different countries. 10/10 I highly recommend it for adserving purposes on WP.