To Reproduce:

1. Open & build the project attached to the post to an iOS 8 device.

2. Click open file & "Allow access", select any image.

3. When you return to the app, the particles in the background are still paused.

This only happens in landscape mode only, if it is changed to Portrait this is no longer reproducible. Also it's only reproducible when the app has not yet been granted access to photo library, you have to rebuild it with a different product name or reset the permissions on the device to reproduce it again.

Issue can be worked around by removing these lines:

if(_didResignActive)
UnityPause(false);

from applicationDidBecomeActive in UnityAppController.mm.