I use Occasions- It's always getting updates (improvements not just bug fixes) and it takes the birthdays from your contact list and adds them automatically. I Highly recommend it. Yes has push notifications and sound as well as customizable backgrounds and Full calender holidays.
I suggest the Calendar app included with your iPod/iPhone. On a serious note, occasions is easily the best.
best birthday reminder app Hello people, There is a better birthday app on AppStore: eAnniversary (only US$ 0.99). eAnniversary will let you track: birthdays and anniversaries, with features to remember you and congratulate the other part. Social networking is also present. Now you can share birthdays and anniversaries with your friends and family in Twitter and Facebook.* You may also update your Google calendar with eAnniversary data, and a lot more features! Check on: http://itunes.apple.com/us/app/eanniversary/id366474659?mt=8 Best regards,
Free Reminder App for iPhone I have been using this app on my iPhone for a while. It is very easy to use and I can see countdown on number of days before the due date arrived. It also will notify when the app is not running. Here is the link: http://itunes.apple.com/us/app/reminder-app/id391438078?mt=8