Try running this simple experiment to see, how using autorelease pools can add up and save you tons of memory. I did, and it really helped.
No autorelease pool for temporary objects:
https://gist.github.com/kmdarshan/ecf28ae0acb576e73b51
Memory Usage:

https://gist.github.com/kmdarshan/b2fb19d6907cd5681b9f
Memory Usage: