What are the best mobile ad formats and the best mobile ad sizes? The question is never old and publishers are still looking for the right answer.

From the best-performing mobile ad sizes to IAB's growing mobile ad units, you'll learn everything to double your advertising revenue on your mobile device.

1) The mobile banner 320×50 is best implemented as a docked/anchor unit. That’s when it performs better regarding CTR. Since it’s a small ad unit, when served as a regular banner, 300×250 and 320×100 units usually outperform it.

2) “Scroller,” an emerging ad unit that fills the screen without covering the entire content is one approach to ad-blocking concerns. According to the IAB’s report, this type of ad format is non-invasive (the users can scroll past them) and has outperformed expandable banners regarding creativity and enjoyment.

3) Medium Rectangle (300×250) remains to be the best performing banner size. Take advantage of the opportunity to implement it above the fold.

4) In-banner Video (IBV) providers favor 300×250 most of the time. They usually pay the best CPMs which you can compete against Header Bidding to push performance up. When running IBV, try to limit it to two units at most to avoid slowing down the page.

Be careful not to overwhelm your users with too many interstitials per user session. It may turn them off, and they may avoid your site altogether in the future. Should you decide to try interstitials or other intrusive ads, remember the guidelines on the previously mentioned Ad Experience Report.

5) The “Large Rectangle” (336×280) is also a top performing ad size as suggested by Google. Make your ad unit flexi by adding it along with your standard mobile ad sizes (e.g., 300×250 / 336×280). It has been proven to perform well when embedded within text content or at the end of articles.

6) Aside from the ad size, one advantageous feature of mobile devices is the location service plus. This makes advertising more relevant to users and potentially generate higher clicks. If you are using an ad server, like Google DFP, geographical targeting will play a significant role. Most ad networks can specify the countries where they have campaigns available.

7) Check your ads for aesthetics. Keep only those ad networks that serve high definition quality creatives and ditch the pixelated ones regardless of the CPM’s they promise. You can’t afford to compromise on user experience. Ads that are non-pixelated tend to yield positive engagement rates and leave a positive impression on users.

8) You can have multiple ad sizes compete in the same ad spot to tighten competition. For instance, you can have a 300×250 spot serve 320×100 and 320×50. When this happens, the smaller advertisements will always align vertically at the top.