The site displays a professional-looking "injection" or "installation" progress bar to mimic a real technical process.
Using unofficial "hack" sites can lead to several security issues: Malware & Phishing: apphack.co cydia
I couldn’t find any verified or legitimate information about a feature called apphack.co related to Cydia. modified app icons
Cydia’s popularity has declined with Apple’s improved iOS security and the rise of (allowed in the EU via DMA regulations). Most modern jailbreaks are semi-untethered and require re-running an app after every reboot. apphack.co cydia
Access to third-party themes, modified app icons, and control center tweaks not available on the Apple App Store. Game Hacks/Cheats: The core focus of AppHacks.co.uk