Instruments is an analysis and testing tool that comes packaged with Xcode, which you can use to dynamically trace and profile iOS application code. The power and flexibility of this tool cannot be understated as it allows you to track one or more processes and examine the collected data in real time. In addition to the many tools that come packaged in Instruments, you can also create and configure your own custom Instrument tools. Most often, you will find yourself using Instruments to track down and repair memory-related issues. Instruments will not present you with a "quick fix" for memory leaks, but it will remove most of the guesswork.
Note
A detailed discussion of Instruments is beyond the scope of this book. For more information on the tools provided by this suite, please see the documentation on each one at https://developer.apple.com/library/mac/documentation/developertools/conceptual/instrumentsuserguide/Introduction/Introduction.html.