I don't live in LA but I visit often. I have found google maps
traffic reports to be quite helpful. There is, however, one point of
confusion. If you checked an hour ago or a few hours ago or even
yesterday, what you see when you bring it up might be the old data.
You must wait for it to update with the latest which could take
anywhere from a few seconds to a few minutes. It isn't obvious you
are looking at the old data becasue you can scroll and zoom. I don't
know if they ever fixed that or not. I now use google maps under iOS
6, but I haven't noticed if it still does the same thing.
Pat