Learn Piano HD 3.0 ($2) - Learn Piano HD 3.0 is a new version of the piano teaching tool for iOS devices. Two of the main features of this upgrade are added support for landscape mode on the iPad, and support for portrait mode on iPhone and iPod touch. An issue has been fixed that would cause the app to crash on on lessons with long text, and another bug fix deals with problems that would occur after watching videos in full screen. [Download - 13.5MB]

Tweet Library 2.0 ($10) - Tweet Library works as an advanced Twitter app with archiving and filtering capabilities. With the latest upgrade the app now requires iOS 5 to run, and is a universal app that works on iPad, iPhone, and iPod touch. Support has been added for Twitter's photo upload, and for saving web pages to Pinboard. Additionally, a new status bar shows recent network activity to Twitter and Tweet Marker. [Download - 1.8MB]

Lyst Ignition 1.2 ($1) - Steel Games has unveiled a new 1.2 version of Lyst Ignition, the iPhone/iPad game where players mix matter to create powerful explosions. The latest upgrade delivers a new game mode called Invasion, where players must stop randomly spawning invaders who are trying to deactivate their matter. Other changes range from minor gameplay improvements to a slightly larger game field on iPad devices. [Download - 32.8MB]

WinZip 1.0 (free) - Recently, one of the most popular file compression tools, WinZip, has become available for iPhone, iPad, and iPod touch devices. The program allows users to open Zip files and Zip attachments from e-mail, browse and view all Zip files, and open encrypted Zip files. Users can also view Zip file attachments from popular webmail sites including Yahoo, Gmail, and Hotmail. [Download - 1MB]

Aaaah Zombies!!! 1.0 ($1) - A new horror adventure-game has been announced for iPhone and iPad devices, called Aaaah Zombies!!!. During the game players take on the role of Pyro, as he mows down waves of different zombies in nine unique levels. Up to eight player classes are available to choose from along with 26 different weapons and six difficulty levels that range from easy to insanely hard. [Download - 51.5MB]