ConcertDiary is an app for iPhone which gives you instant access to your recent and future planned concerts. You can add concerts you are attending and review concerts you have attended. In addition you can add pictures of the concerts and rank them as of how good they were. You can also instant share an invite to all your friends via E-mail or share what you thought of the concert. Also a neat feature is that you can add the concert to you iPhone calendar so you can be reminded of when it is. There is of course also a history function and a search function for those who attend many concerts. ;)
When you add a new concert, you set the time and date of the concert, the concert name/band, place and comments.
Retina support!