I cannot believe how much of a speed difference there is by turning on "increased contrast"!
Sorry if this is old or has been beaten to death by I thought I would try and share!
So, I have noticed on my iPhone 5 that sometimes the transitions are slow and certain apps would just hang up. I thought it might be due to the fact that I have only 2 GB or so left on my 32 GB iPhone 5, but I did a quick search and found out that one "trick" is to turn on increased contrast under settings. Increased contrast is where it will nullify most of that translucent/transparent crap that iOS 7 introduced. I never really cared for it and I actually prefer a more "flat" design and I like being able to differentiate my notification bar from my background more clearly. I noticed the overall performance of the phone was a lot speedier (similar to iOS 6 imo). I told my sisters (who both have iPhone 4s') and they noticed a great speed bump as well.
Anyways, I figured I would spread some knowledge that seems pretty academic but just easily overlooked. Have you guys noticed any speed difference by turning on that setting or can you live with that transparency in iOS 7? Any other "tricks" for speed enhancement?