There are already some reviews of the LiveNation App here, here, and here. I’m going to give you the link and a screen capture.

livenation-app-screenshot

LiveNation does make available presales on their app, which you can get for free: LiveNation App

UPDATE : Seems the livenation app is “Generally terrible” according to many reviewers on Bad App Reviews – but take this with a grain of salt as there is a solid 4.5 stars on the app store as of this writing.