Cydia is an open, decentralized platform that helps you install software packages hosted by independent repositories, also called sources.
Each source chooses the packages it hosts, how its pages look, and how it is run. They may choose to have ads.
Cydia includes a few default sources (BigBoss, Cydia/Telesphoreo, Dev Team, ModMyi, and ZodTTD & MacCiti) that host thousands of popular and useful packages.
Anyone can run their own source( a source is basically a specialized website viewable by Cydia)
you are free to add un-trusted third-party sources, but you do that at your own risk(not recommended). Packages from third-party sources may not have the same strict quality control as the packages in default sources, and we do not screen them.