Zenity - Zenity is a tool that allows you to display GTK dialog boxes in commandline and shell scripts.
Zoom - Equip your team with tools designed to collaborate, connect, and engage with teammates and customers, no matter where you’re located, all in one platform.
Glade - Glade is a RAD tool to enable quick & easy development of user interfaces for the GTK+ toolkit...
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Yad - Yad (yet another dialog) is a fork of Zenity with many improvements, such as custom buttons...
Snarl - Snarl is a notification system for Windows.