Apper is a free and opensource Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 front end of the PackageKit

PackageKit

PackageKit is an open source and free suite of software applications designed to provide a consistent and high-level front end for a number of different package management systems...

 application for the KDE

KDE

KDE is an international free software community producing an integrated set of cross-platform applications designed to run on Linux, FreeBSD, Microsoft Windows, Solaris and Mac OS X systems...

 desktop.
Apper was originally named KPackageKit however, understanding the complexity of the meaning of "Package

Package

Package can refer to:* Packaging and labeling* Package testing* Mail item larger than a letter* Chip package or chip carrier, in electronics, the material added around a component or integrated circuit to allow it to be handled without damage and incorporated into a circuit* Automotive package, in...

" for Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 new comers it was renamed Apper (after the name AptGet be considered as well) to avoid the "Package" word.

Apper also has one main difference if compared with the old KPackageKit, Apper has the ability to list applications instead of listing only packages. This makes it a lot more user friendly and allows the user to search and install applications without the complexity of dealing with Packages and dependencies.. Beside installation of new applications it also allows easy removal and update. It can be compared to the Ubuntu Software Center

Ubuntu Software Center

Ubuntu Software Center is a computer program for browsing, installing and removing software on the Ubuntu operating system. Based upon the GNOME application, gnome-app-install, which is similar in function and appearance, it serves as a GTK+ graphical user interface front-end to the Advanced...

 in some degrees as well as to the AppStream

AppStream

AppStream is an agreement between major GNU/Linux vendors to create a common application installer for Linux and one unified application installation GUI and sharing of metadata....

 project.

Apper has been adopted by a few distros such as Fedora and OpenSuse

OpenSUSE

openSUSE is a general purpose operating system built on top of the Linux kernel, developed by the community-supported openSUSE Project and sponsored by SUSE...

12.1, to name a few.