Yad - Yad (yet another dialog) is a fork of Zenity with many improvements, such as custom buttons...

AfterShip - AfterShip is the shipment tracking API for ecommerce businesses and marketplaces.

Zenity - Zenity is a tool that allows you to display GTK dialog boxes in commandline and shell scripts.

TrackChecker Mobile - TrackChecker Mobile app features tracking of parcels and online orders, so users don’t have to worry about losing a package by tracking the parcel right on their mobile phone screen.

Glade - Glade is a RAD tool to enable quick & easy development of user interfaces for the GTK+ toolkit...

Track24 - Track24 app assists you in tracking the packages of more than 600 international courier and postal services from all around the globe.