"given the switch to 64-bit iOS 7 seems to be causing 20-30% higher memory consumption"
I've not read about this. Can you cite a source?
I've not read about this. Can you cite a source?
Most apps are not using tens of megabytes for pointer based graph-structures etc. or code.
They are however using loads of megabytes for image data, offscreen buffers, etc.
So I doubt that 64-bit changes much.