Not every tweak or theme is automatically available once you jailbreak your iOS device and install the Cydia application. For certain tweaks, you'll need to manually add its source, which is simply a web address linked to repository where the tweaks are hosted.
The whole process will require a few steps to complete. Remember you will need an internet connection and a valid repo link to do so.
Cydia is installed with all its default repos and it works perfectly. For others though, the story is a different one. There have been a number of people who jailbreak who have found that one of the main default repositories is not there and it’s the one they really want.
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