0install
Run or manage Zero Install programs
Package Organizer
Manages software installed from source code

Lubuntu Software Center
Lets you choose from thousands of applications available for Ubuntu

Debian Package Search
Search for packages and view package information
Ubuntu Software Center
Lets you choose from thousands of applications available for Ubuntu

Synaptic Package Manager
Install, remove and upgrade software packages

Software Boutique
Discover and install software from a collection that compliments Ubuntu MATE.
Ubuntu Kylin Software Center
Ubuntu Kylin software management tools

Banner Designer
Design the featured banners for GNOME Software

Application Installer
Add, remove or update software on this computer
Ubuntu Software
Add, remove or update software on this computer
Packages
Add or remove software installed on the system

Xfpack
A simple package manager for Xfe
Xfp
A simple package manager for Xfe
Apper
Application to get and manage software
Apper Installer
Application to get and manage software
Limba Package Installer
Tool to install software from 3rd-party sources
AppCenter
Browse and manage apps

dnfdragora Package Installer
Install local packages on the system

dnfdragora
A graphical front end for installing, removing and updating packages

dnfdragora-updater
Automatically check for updates and notify
AptURL
Install a package
Kylin Software Center
Kylin software management tools

Package Update Indicator Preferences
Edit the Preferences for Package Update Indicator

Check Apt GPG
Check and install missing apt GPG keys

MX Check Apt GPG
Check and install missing apt GPG keys

MX Fix GPG keys
Check and install missing apt GPG keys
Synaptic-Testing
Launch Synaptic with Test Repo Enabled

YaST Software
Install/Remove Software
Sideload
Install apps downloaded from the Internet