In OS X Lion and iOS 6 Apple added a new way to layout views, Auto Layout. This is a very powerful system that will handle a lot of the work and overhead of arranging your views. A well defined layout can make many headaches disapear entirely. However, it is a bit…quirky…to say the least.1
I recommend that you read the guide to the visual format language before going on.
This post will discuss the various options that you can set in
constraintsWithVisualFormat:options:metrics:views:. These options affect
how the views described in the format string are to be aligned with each other.