Readdle, one of the App Store’s most successful productivity app developers, is celebrating its fourth birthday today with a big app sale and an iPad 2 giveaway. With awesome treats like these, doesn’t it actually kind of feel like your birthday instead?

Readdle was founded on August 1, 2007, and since that time the Ukraine-based app developer and publisher has delivered over 3,150,000 copies of their various apps to iPhone and iPad users all around the world. To celebrate this grand achievement, the team is giving back to all of those that have made this fantastic run possible by marking down their entire collection of productivity and business apps by a hefty 30% for the next 48 hours.

iPhone:

Universal:

iPad:

Those certainly are some great deals, but this next piece of news is sure to be the icing on the birthday cake!

Readdle will also be giving away a 16GB Wi-Fi iPad 2 ($499) each of the next four days! To have a chance at nabbing yourself one of these beautiful big screen devices, just follow Readdle on Twitter and then tweet the following message:

30% sale for all iOS @Readdle apps. Follow and Retweet to win one of 4 iPads. http://readdle.com/4years #Giveaway

Readdle will be choosing their four winners at random and posting the results on their website, so make sure to check back and see if you are one of the lucky four.

And here is a little extra motivation for those thinking they don’t have a chance at winning an iPad 2. Last year an AppAdvice reader, @mattbanks, actually won one of the three iPads Readdle was giving away for their third birthday celebration, so hopefully one of you can be the next reader to represent us. Good luck!