Unity3D app crashes out after error "Warning -> ApplicationDidReceiveMemoryWarning'

Not sure what the cause of this is, I thought it might be memory running out but attempting to limit the amount of memory used hasn’t helped at all, any ideas?

Hard to say without more information, but on iOS that warning is just a call that asks apps to release some memory that they don’t need right that second. It might not be related to your app to crashing though. A good start would be to run your app with the profiler and see if there are some parts that are memory intensive that you could optimize. If cutting some things out of your app fixes the memory issue but it still crashes at least you know you have another issue to address.

It’s highly likely you are using memory you don’t know about if you think you’ve limited it and then still receive that message.

If you receive applicationDidReceiveMemoryWarning then crash it is very likely to be your application being terminated by iOS for using too much memory.