We have encountered a fully reproducible crash that is being caused by MRAID ads. The crash information can be found here: http://crashes.to/s/4d981bd3013
Note that the crash is actually hitting gpus_ReturnNotPermittedKillClient, which indicates that the application is attempting to use the GPU from the background.
In testing, I have been able to track this down to MRAID creatives being the cause of this issue. What appears to be happening is that the MoPub implementation for MRAIDs does not take the application state into account. I have been able to verify that multiple “loads” of web content can easily happen after the application enters the background. Any one of these could potentially trigger a GPU request, which crashes the application.
I made an attempt to block the MRAID calls from continuing after the app entered the background, but was unable to get the fix to work. No matter what I did, it appears that the MRAID code continued to allow loading of ad content.
An update should be made to the MRAID adaptor to stop all running ad content when the application enters the background so as not to cause any crashes of the application.