You might be confused. Is Cydia back? Is this a new tweak? Can you install Cydia without a computer?

To actually jailbreak, you still need a dedicated jailbreak tool (like TrollStore or palera1n ). Once the jailbreak is complete, then Cydia appears on your home screen. The Cydia IPA is just the launcher; it isn't the key. So why are people still searching for "Cydia IPA"? Because the iOS hacking scene has shifted.

cydia-ipa-guide