I've integrated HeyZap ads in my application; both incentiviced and banner ads.
I've noticed that after integrating an IAP, the banner ads from Admob no longer show and I'm not not seeing any incentiviced ads directly from HeyZap (I still see AdColony and Unity ads through the mediation).
In the android logcat I'm seeing the message Heyzap: Ads disabled because of an IAP. Unfortunately I haven't been able to find any documentation on this matter.
I would be grateful if anyone has an explanation. Thanks.
In your app-specific Publisher Settings on the Heyzap Dashboard there is a value called In App Purchase Ad Timeout. In your case it seems you want this value to be 0. It may take some time for this value to go in to effect and it will require you to restart your application while testing.
I hope this helps, let me know if you are still seeing this behavior after modifying this setting.
Source: am heyzap engineer