Cydia
Created by Jay Freeman, Cydia is a platform for users who have jailbroken their iOS devices. It allows them to find, download, and install apps and tweaks unavailable on the official Apple App Store. These apps and tweaks often give you more ways to customize your device, add extra features, and do things that regular, non-jailbroken machines can't do.
Think of Cydia as a manager for these apps and tweaks. It helps you look for them, install them, and keep track of them. You can search for specific apps or tweaks, read about what they do, and add or remove them whenever you want.
Cydia depends on places called repositories (repos for short) to keep all these apps and tweaks. Repositories are like collections of apps and tweaks that you can get through Cydia. Some well-known ones are BigBoss, ModMyi, and ZodTTD & MacCiti. You can also add your custom reports to get even more stuff.
People love Cydia because it gives them many ways to change and improve their iOS devices. You can make your device look different, add new functions, and make it work better. For example, you can change how the iPhone or iPad looks, add new gestures for easier control, or make app icons move excellently. People who use Cydia often share their favorite changes and tips on websites, blogs, and social media.
Official website: https://www.cydiafree.com/