Best practice testing the iOS application development with Instruments-Collection of common programming errors

I wonder how the professional application that provided to customer is such elegant , smooth and less or no application crash. because I always see the problem is mostly about memory leaking, NSZombie or not good enough performance.

I see it’s great to fix some problem with Instruments Tool. But I just be familiar with memory leaks and zombie template. Of course, I think there are other interesting tool to trace and fix our application better. (System usage, Automation Testing, etc.. Any ideas?)

My question : What’s the best strategy to sharp your application with Instruments? Recommend instruments template or any suggestion?

Let’s share your experience and discuss!

*UPDATE : * May I ask more question, Should I edit this question to the wiki? It should be more than question that we can share strategy.