What is the ad mediation service?
Ad mediation is the managing of, and arbitration between, multiple ad providers to try and ensure that the ad that will earn the app publisher the most money is shown and potential ad space is not wasted.
The first solution to this problem came from the community in the form of AdRotator and it was initially very popular. Later, Microsoft released their own solution and it has now become much more common for people to use this due to its integration with the dev centre.
Many developers wish to monetize their apps with advertising and it’s common for them to use ads from multiple networks to achieve this. This is because some ad networks have more ad inventory in one territory than another or are able to offer a higher eCPM for the impressions.
Because of the way AdDuplex works, there will always be an ad that we can serve. This means that as long as there is a network connection we can display an ad. No other ad providers can make this claim and can deliver a typical fill rate of anywhere between 10 and 60 percent depending on varying factors including app, language and country.
This makes AdDuplex an excellent option when considering ad mediation.
One of the aims of ad mediation is to ensure that none of the available ad inventory goes to waste. Even if you’re not using AdDuplex as part of your user acquisition strategy it can be useful to ensure that you are not wasting your ad inventory. It’s better to show a cross promotion ad that may lead to you obtaining a new user than it is to let ad inventory go to waste. For this reason, we believe, you should always include AdDuplex as part of your ad mediation configuration.
How to set it up
Microsoft have some good general instructions on adding and using the ad mediation control but here are some specifics around the AdDuplex aspect.
Firstly there’s the things you’ll need to do to get set up:
Now for the configuration.
AdDuplex ads are configured in the same way as other ad providers. In Visual Studio, right click on the project References and select “Add Connected Service…”
If there are multiple services available to you, select Ad Mediator and press the Configure button to configure your mediation. Note that connected services available will depend on the version of Visual Studio you are using so you may see something slightly different to the screenshots here.
To tell the mediator that you wish to use AdDuplex, click on the “Select ad networks” option and check the appropriate box.
When you click the OK button the appropriate NuGet package will be downloaded and included in the project.
To configure the control/ads that will be displayed, highlight the AdDuplex entry and click the Configure link.
Here you should set the values you can copy from the client area website.
When you’re ready to submit your app to the store the submission process identifies that you are using ad mediation and provides a way to view and adjust the configuration.
When multiple networks are specified through Visual Studio the ads are displayed in a “round-robin” fashion. That is that the mediator will try and show an ad from one network, then an ad from the next, and so on. On the website you can tailor the configuration to be much more specific about the weight you give to each network.
In the above example the ad mediator is set to show AdDuplex ads 20% of the time but if we wanted to have AdDuplex ads only shown when paid ads aren’t available it should be set to backup.
Addressing some common Issues
Set the app key and ad unit id correctly
When settings the app key and ad unit id, make sure you set them the right way round. The app key is a GUID and is the longer of the two. The ad unit id is numeric.
In earlier versions of the ad mediation control it was only possible to set the “App Id” which was equivalent to the ad unit id. That confusion should now no longer be a problem as the ad mediation configuration allows setting both values.
Problems testing on the emulator
Some people have had issues getting ads to display when running in the emulator. There is nothing to stop ads displaying in the emulator or need for a special configuration to run in the emulator (like there is with Microsoft Advertising) however, we always recommend testing on an actual device.
Control size
You may experience problems with setting the ad height and width in a Windows 8/8.1 app and having it display correctly on devices with some resolutions. Just using ads with the default (auto) size and not setting the height and width of the control explicitly, should avoid this.
Setting the App Key and Ad Unit Id
It’s possible to set the values you need to use to configure your ad units on the dev centre website when submitting your app. We recommend not doing this and instead setting these values though Visual Studio (as above) to allow you to test that they’ve been set correctly.
After updating the NuGet package
When configuring the ad mediator settings the AdDuplex NuGet package will automatically be downloaded and included in the project. If an update to the AdDuplex NuGet package is later released we do all we can to make sure that it will still be compatible. If you manually update the NuGet package there’s a possibility of incompatibility between the AdDuplex library and the AdMediator library. If you get errors after updating one but not the other then we recommend reverting back to a last known good state or using the version of the AdDuplex control that is installed by ad mediator.
What about Windows 10?
The Ad Mediator service for Universal Windows Platform (UWP) apps currently only supports Microsoft Advertising as a provider.
We’re working with Microsoft to add the AdDuplex control as soon as possible but if you want to put the AdDuplex control in your UWP app now you can do this directly as we announced in July.
![797x435[4]](https://adduplex.files.wordpress.com/2016/05/797x4354.png?w=600&h=327 "797x435[4]")
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