The use of ad mediation in mobile apps has become the mainstream in the last few years. One ad-network can’t have demand to give you good fill-rates and high CPMs for all your user segments and all the geographic locations where you have users. In addition, mediation allows you to add more ad-networks and increase demand for your ad inventory. As you might remember from “Introduction to Economics” – with fixed supply and increasing demand the price goes up. If you want to evaluate different mediation platforms check this post comparing 6 different mediation platforms.
Use placements/zones/areas for placements
Most mediation platforms has a feature called placements or zones or areas. This is designed so that if you have different areas where ads are presented in your app, you can give them names when implementing the SDK and later on refer to them from the mediation platform. This has a few benefits:
- You will be able to see reporting for each placement separately
- The mediation auto-pilot will optimize for each placement individually giving the optimization more precision
- When setting up a manual waterfalls you can set specific one for each placement
Use placements for segments, testing, impression frequency and ad types
Advanced publishers often use the placements feature for other purposes to enjoy the same benefits mentioned above. Here are a few ideas:
Segments – Let’s say that you could create a segment of users who respond well to videos it would have made sense to show them only video ads. Alternatively, if you had a segment of users that don’t perform well for CPI campaigns – it would make more sense to create a waterfall for these users that gives higher pirority for brand oriented ad-networks such as Mediabrix and Hyper MX.
Testing – optimizing and trying different things is a standard practice in mobile these days. The only way to test different setups is to differentiate group A from group B by duplicating all your placements and marking them A and B repsectively.
Impression frequency – serving different placement every time an ad is presented to the same unique users can give you visibility into your eCPM decay and allow you to optimize your impression frequency.
Ad types – this one goes without saying. Differentiate your videos from interestitials.
Some of the advanced segments mentioned above requires the use of SOOMLA TRACEBACK which also allows to test different ad setups and monitor eCPM decay without jumping through hoops
Don’t put all your eggs in the auto-pilot basket
Most mediation platforms have 3 modes:
- Automatically allowing the mediation platform to select the best provider
- Manually configuring the waterfall
- Mixed – manual for the top countries and automatic for smaller ones
The automatic approach means that the mediation platform will check each of the ad networks every day to see which one provided the best eCPM and then prioritize the waterfall based on that number. The problem with the auto-pilot approach is that it is based on yesterday’s data. Moreover, in many cases the lower performing network will get switched to the top of the waterfall due to randomness in small numbers. The companies that make the most amount of ad revenue in the world often takes things into their own hands. You should at least experiment with this approach.
Disable the network that gave you the mediation
Most mediation platforms are owned by ad-networks. This creates an immediate conflict of interest. The mediation should be an unbiased, neutral 3rd party while the ad-networks compete with each other for more inventory. What is a publisher to do? Try to find a setting in your mediation platform that eliminates the owning ad-network from the auction. This way you are still enjoying a free mediation but you can be sure that it’s neutral. Important note – make sure you have a catch-all ad network or an SSP if you use this trick. Otherwise you will end up with a low fill rate.
Multiple CPM floors to force ad-network bidding
This is the most advanced trick in this post and requires you to do some prep work on the ad-networks. Basically every ad-network can apply a CPM floor. Some of them allow you to control this from their dashboard while others have the control on their side so you have to call and ask for it. What you want to do with this setting is to create 2 or 3 CPM floor levels under different App IDs or placements and then enter them into the mediation in different positions in the waterfall. Let’s see this simplified example with 2 ad-networks.
Example of a waterfall multiple CPM floors:
- 1st priority – network A floor $20
- 2nd priority – network B floor $20
- 3rd priority – network A floor $15
- 4th priority – network B floor $15
- 5th priority – network A floor $10
- 6th priority – network B floor $10
This means that if either ad-network has an ad that will pay more than $20 they will get to serve it. If none has it, the waterfall goes down to 3rd and 4th priority and checks if there is an ad that will pay $15 or more and so forrth. This method forces ad-networks into an auction that increases the price you get for your inventory.