It looks like you are asking about (likely the iOS jailbreak tweak for installing unsigned/fakesigned IPA files) and a repository that has been patched .
AppSync Unified does not work on non-jailbroken devices. If you are not jailbroken, look into TrollStore if your iOS version supports it, as it provides similar functionality without a full jailbreak. appsync repo patched
AppSync Unified (Cydia / Sileo / Zebra) Patch ID: AS-2025-04-18 Status: ✅ Patched & Redeployed AppSync It looks like you are asking about