Google adwords display network is a great way to get a ton of impressions on your banner ads with some decent targeting. I’d recommend you look into a programmatic ad buy if you are looking for very detailed targeting and higher quality traffic, however sometimes google adwords campaigns are more affordable and get you the results you want.
One thing to be careful with google adwords, especially display campaigns, is that their network has a ton of adsense placements in “poorly design” mobile apps and websites that are not ideal for obtaining traffic from. Most of the time when someone is using an app they don’t want to click on an advertisement. In fact most of the clicks from an ad in an app should be considered a “mistake” because the ad popped up for the user or something similar.
Here is a quick tutorial on how to remove these google apps and ad placements from your campaigns in adwords to avoid paying for all of the poor quality clicks they will get. The trick is to exclude adsenseformobileapps.com from your placements list to avoid the adsense placements people have set up in either mobile apps or mobile platforms.
https://youtu.be/yz2_gWtnzKY