CustomDia is a tweak in Cydia, that will not allow you to improve and add functionality to Cydia. A section in the settings allow you to activate Landscape (like iPad), remove sources "pirate" of alerts, to hide its installed tweak and spend the early loading page and other..
The button "about" a was replaced by a button in which you'll be able to do a respring and refresh your sources.
Configure options from Settings.